China National Standards

China Y GB Standards English PDF List


GB standards are the China national standards; Prefix code GB are Mandatory standards, GB/T are Recommended standards; All products or service must be compliance with GB standards; If you want to export products or services to huge Chinese market, need ensure they are meet the requirements of GB china national standards;  We provide Chinese GB standards and English version GB standards  Lookup, Translate, Download, Imported Commodity GB standards Testing and Compliance review services.
  •  China "Y" GB Standards English PDF List:
  • Standard  Code Standard Title Standard Class Order
    GB/T 8151.20-2012 Methods for chemical analYsis of zinc concentrates - Part 20:Determination of copper,lead,iron,arsenic,cadmium antimony, calcium,magnesium contents - Inductively coupled plasma atomic emission spectrometry
    锌精矿化学分析方法 第20部分:铜、铅、铁、砷、镉、锑、钙、镁量的测定 电感耦合等离子体原子发射光谱法
    China National Standards
    Y

    English PDF
    GB/T 8151.19-2012 Methods for chemical analYsis of zinc sulfide concentrates - Part 19:Determination of silver and gold contents - Fire assay and flame atomic absorption spectrometric method using scorification or cupellation
    锌精矿化学分析方法 第19部分:金和银含量的测定 铅析或灰吹火试金和火焰原子吸收光谱法
    China National Standards
    Y

    English PDF
    GB/T 8151.18-2012 Methods for chemical analYsis of zinc concentrates - Part 18: Determination of zinc content - Ion-exchange/ Na2EDTA titrimetric method
    锌精矿化学分析方法 第18部分:锌量的测定 离子交换-Na2EDTA滴定法
    China National Standards
    Y

    English PDF
    GB/T 5247-2012 ElectrolYtic nickel powder
    电解镍粉
    China National Standards
    Y

    English PDF
    GB/T 5231-2012 Designation and chemical composition of wrought copper and copper alloYs
    加工铜及铜合金牌号和化学成分
    China National Standards
    Y

    English PDF
    GB/T 5106-2012 Straight cYlindrical involute splines - Gauge
    圆柱直齿渐开线花键 量规
    China National Standards
    Y

    English PDF
    GB/T 4436-2012 Wrought aluminum and aluminum alloY tubes - Dimensions and deviations
    铝及铝合金管材外形尺寸及允许偏差
    China National Standards
    Y

    English PDF
    GB/T 4324.9-2012 Methods for chemical analYsis of tungsten - Part 9: Determination of cadmium content - Inductively coupled plasma atomic emission spectrometry and flame atomic absorption spectrometry
    钨化学分析方法 第9部分:镉量的测定 电感耦合等离子体原子发射光谱法和火焰原子吸收光谱法
    China National Standards
    Y

    English PDF
    GB/T 4324.7-2012 Methods for chemical analYsis of tungsten - Part 7: Determination of cobalt content - Inductively coupled plasma atomic emission spectrometry
    钨化学分析方法 第7部分:钴量的测定 电感耦合等离子体原子发射光谱法
    China National Standards
    Y

    English PDF
    GB/T 4324.6-2012 Methods for chemical analYsis of tungsten - Part 6: Determination of iron content-1,10-phenanthroline spectrophotometry
    钨化学分析方法 第6部分:铁量的测定 邻二氮杂菲分光光度法
    China National Standards
    Y

    English PDF
    GB/T 4324.5-2012 Methods for chemical analYsis of tungsten - Part 5: Determination of arsenic content - Hydrogenate atomic absorption spectrometry
    钨化学分析方法 第5部分:砷量的测定 氢化物原子吸收光谱法
    China National Standards
    Y

    English PDF
    GB/T 4324.4-2012 Methods for chemical analYsis of tungsten - Part 4: Determination of antimony content - Hydrogenate atomic absorption spectrometry
    钨化学分析方法 第4部分:锑量的测定 氢化物原子吸收光谱法
    China National Standards
    Y

    English PDF
    GB/T 4324.3-2012 Methods for chemical analYsis of tungsten - Part 3: Determination of tin content - Hydrogenate atomic absorption spectrometry
    钨化学分析方法 第3部分:锡量的测定 氢化物原子吸收光谱法
    China National Standards
    Y

    English PDF
    GB/T 4324.28-2012 Methods for chemical analYsis of tungsten - Part 28: Determination of molybdenum content - The thioyanate spectrophotometry
    钨化学分析方法 第28部分:钼量的测定 硫氰酸盐分光光度法
    China National Standards
    Y

    English PDF
    GB/T 4324.27-2012 Methods for chemical analYsis of tungsten - Part 27::Determination of carbon content - High frequency combustion-infrared absorption method
    钨化学分析方法 第27部分:碳量的测定 高频燃烧红外吸收法
    China National Standards
    Y

    English PDF
    GB/T 4324.26-2012 Methods for chemical analYsis of tungsten - Part 26: Determination of nitrogen content - Pulse heating inert gas fusion-thermal conductive method and the Nessler reagent spectrophotometry
    钨化学分析方法 第26部分:氮量的测定 脉冲加热惰气熔融-热导法和奈氏试剂分光光度法
    China National Standards
    Y

    English PDF
    GB/T 4324.25-2012 Methods for chemical analYsis of tungsten - Part 25: Determination of oxygen content - Pulse heating inert gas fusion-infrared absorption method
    钨化学分析方法 第25部分:氧量的测定 脉冲加热惰气熔融-红外吸收法
    China National Standards
    Y

    English PDF
    GB/T 4324.24-2012 Methods for chemical analYsis of tungsten - Part 24: Determination of phosphorus content - Molybdemum blue photometry
    钨化学分析方法 第24部分:磷量的测定 钼蓝分光光度法
    China National Standards
    Y

    English PDF
    GB/T 4324.23-2012 Methods for chemical analYsis of tungsten - Part 23: Determination of sulfur content - The combustion-conductometric titration and high frequency combustion-infrared absorption method
    钨化学分析方法 第23部分:硫量的测定 燃烧电导法和高频燃烧红外吸收法
    China National Standards
    Y

    English PDF
    GB/T 4324.22-2012 Methods for chemical analYsis of tungsten - Part 22: Determination of manganese content - Inductively coupled plasma atomic emission spectrometry
    钨化学分析方法 第22部分:锰量的测定 电感耦合等离子体原子发射光谱法
    China National Standards
    Y

    English PDF
    GB/T 4324.2-2012 Methods for chemical analYsis of tungsten - Part 2: Determination of bismuth content - Hydrogenate atomic absorption spectrometry
    钨化学分析方法 第2部分:铋量的测定 氢化物原子吸收光谱法
    China National Standards
    Y

    English PDF
    GB/T 4324.21-2012 Methods for chemical analYsis of tungsten - Part 21: Determination of chromium content - Inductively coupled plasma atomic emission spectrometry
    钨化学分析方法 第21部分:铬量的测定 电感耦合等离子体原子发射光谱法
    China National Standards
    Y

    English PDF
    GB/T 4324.20-2012 Methods for chemical analYsis of tungsten - Part 20: Determination of vanadium content - Inductively coupled plasma atomic emission spectrometry
    钨化学分析方法 第20部分:钒量的测定 电感耦合等离子体原子发射光谱法
    China National Standards
    Y

    English PDF
    GB/T 4324.19-2012 Methods for chemical analYsis of tungsten - Part 19: Determination of titanium content - The diantipyrylmethane photometric spectrophtometry
    钨化学分析方法 第19部分:钛量的测定 二安替比林甲烷分光光度法
    China National Standards
    Y

    English PDF
    GB/T 4324.18-2012 Methods for chemical analYsis of tungsten - Part 18: Determination of potassium content - Flame atomic absorption spectrometry
    钨化学分析方法 第18部分:钾量的测定 火焰原子吸收光谱法
    China National Standards
    Y

    English PDF
    GB/T 4324.17-2012 Methods for chemical analYsis of tungsten - Part 17: Determination of sodium content - Flame atomic absorption spectrometry
    钨化学分析方法 第17部分:钠量的测定 火焰原子吸收光谱法
    China National Standards
    Y

    English PDF
    GB/T 4324.16-2012 Methods for chemical analYsis of tungsten - Part 16: Determination of loss content on ignition - Gravimetric method
    钨化学分析方法 第16部分:灼烧损失量的测定 重量法
    China National Standards
    Y

    English PDF
    GB/T 4324.14-2012 Methods for chemical analYsis of tungsten - Part 14: Determination of residue content after chloride volatility - Gravimetric method
    钨化学分析方法 第14部分:氯化挥发后残渣量的测定 重量法
    China National Standards
    Y

    English PDF
    GB/T 4324.12-2012 Methods for chemical analYsis of tungsten - Part 12: Determination of silicon content - Chlorization-molybdenum blue spectrophotometry
    钨化学分析方法 第12部分:硅量的测定 氯化-钼蓝分光光度法
    China National Standards
    Y

    English PDF
    GB/T 4324.1-2012 Methods for chemical analYsis of tungsten - Part 1: Determination of lead content - Flame atomic absorption spectrometry
    钨化学分析方法 第1部分:铅量的测定 火焰原子吸收光谱法
    China National Standards
    Y

    English PDF
    GB/T 4324.11-2012 Methods for chemical analYsis of tungsten - Part 11: Determination of aluminum content - Inductively coupled plasma atomic emission spectrometry
    钨化学分析方法 第11部分:铝量的测定 电感耦合等离子体原子发射光谱法
    China National Standards
    Y

    English PDF
    GB/T 4324.10-2012 Methods for chemical analYsis of tungsten - Part 10: Determination of copper content - Flame atomic absorption spectrometry
    钨化学分析方法 第10部分:铜量的测定 火焰原子吸收光谱法
    China National Standards
    Y

    English PDF
    GB/T 4103.9-2012 Methods for chemical analYsis of lead and lead alloys - Part 9: Determination of calcium content
    铅及铅合金化学分析方法 第9部分:钙量的测定
    China National Standards
    Y

    English PDF
    GB/T 4103.8-2012 Methods for chemical analYsis of lead and lead alloys - Part 8: Determination of tellurium content
    铅及铅合金化学分析方法 第8部分:碲量的测定
    China National Standards
    Y

    English PDF
    GB/T 4103.7-2012 Methods for chemical analYsis of lead and lead alloys - Part 7: Determination of selenium content
    铅及铅合金化学分析方法 第7部分:硒量的测定
    China National Standards
    Y

    English PDF
    GB/T 4103.6-2012 Methods for chemical analYsis of lead and lead alloys - Part 6: Determination of arsenic content
    铅及铅合金化学分析方法 第6部分:砷量的测定
    China National Standards
    Y

    English PDF
    GB/T 4103.5-2012 Methods for chemical analYsis of lead and lead alloys - Part 5: Determination of bismuth content
    铅及铅合金化学分析方法 第5部分:铋量的测定
    China National Standards
    Y

    English PDF
    GB/T 4103.4-2012 Methods for chemical analYsis of lead and lead alloys - Part 4: Determination of iron content
    铅及铅合金化学分析方法 第4部分:铁量的测定
    China National Standards
    Y

    English PDF
    GB/T 4103.3-2012 Methods for chemical analYsis of lead and lead alloys - Part 3: Determination of copper content
    铅及铅合金化学分析方法 第3部分:铜量的测定
    China National Standards
    Y

    English PDF
    GB/T 4103.2-2012 Methods for chemical analYsis of lead and lead alloys - Part 2: Determination of antimony content
    铅及铅合金化学分析方法 第2部分:锑量的测定
    China National Standards
    Y

    English PDF
    GB/T 4103.13-2012 Methods for chemical analYsis of lead and lead alloys - Part 13: Determination of aluminium content
    铅及铅合金化学分析方法 第13部分:铝量的测定
    China National Standards
    Y

    English PDF
    GB/T 4103.12-2012 Methods for chemical analYsis of lead and lead alloys - Part 12: Determination of thallium content
    铅及铅合金化学分析方法 第12部分:铊量的测定
    China National Standards
    Y

    English PDF
    GB/T 4103.1-2012 Methods for chemical analYsis of lead and lead alloys - Part 1: Determination of tin content
    铅及铅合金化学分析方法 第1部分:锡量的测定
    China National Standards
    Y

    English PDF
    GB/T 4103.11-2012 Methods for chemical analYsis of lead and lead alloys - Part 11: Determination of zinc content
    铅及铅合金化学分析方法 第11部分:锌量的测定
    China National Standards
    Y

    English PDF
    GB/T 4103.10-2012 Methods for chemical analYsis of lead and lead alloys - Part 10: Determination of silver content
    铅及铅合金化学分析方法 第10部分:银量的测定
    China National Standards
    Y

    English PDF
    GB/T 3884.9-2012 Methods for chemical analYsis of copper concentrates - Part 9: Determination of arsenic and bismuth contents - Hydride generation- atomic fluorescence spectrometry method The potassium bromate titration method and The silver diethyl dithiocarbamate photom
    铜精矿化学分析方法 第9部分:砷和铋量的测定 氢化物发生-原子荧光光谱法、溴酸钾滴定法和二乙基二硫代氨基甲酸银分光光度法
    China National Standards
    Y

    English PDF
    GB/T 3884.8-2012 Methods for chemical analYsis of copper concentrates - Part 8: Determination of zinc content - Na2EDTA titration method
    铜精矿化学分析方法 第8部分:锌量的测定 Na2EDTA滴定法
    China National Standards
    Y

    English PDF
    GB/T 3884.7-2012 Methods for chemical analYsis of copper concentrates - Part 7: Determination of lead content - Na2EDTA titration method
    铜精矿化学分析方法 第7部分:铅量的测定 Na2EDTA滴定法
    China National Standards
    Y

    English PDF
    GB/T 3884.6-2012 Methods for chemical analYsis of copper concentrates - Part 6: Determination of lead,zinc,cadmium and nickel content - Flame atomic absorption spectrometry method
    铜精矿化学分析方法 第6部分:铅、锌、镉和镍量的测定 火焰原子吸收光谱法
    China National Standards
    Y

    English PDF
    GB/T 3884.5-2012 Methods for chemical analYsis of copper concentrates - Part 5: Determination of fluoride content - Ion selective electrode method
    铜精矿化学分析方法 第5部分:氟量的测定 离子选择电极法
    China National Standards
    Y

    English PDF
    GB/T 3884.4-2012 Methods for chemical analYsis of copper concentrates - Part 4: Determination of magnesium oxide content - Flame atomic absorption spectrophotometry method
    铜精矿化学分析方法 第4部分:氧化镁量的测定 火焰原子吸收光谱法
    China National Standards
    Y

    English PDF
    GB/T 3884.3-2012 Methods for chemical analYsis of copper concentrates - Part 3: Determination of sulfur content - Gravimetric method and Combustion-titration method
    铜精矿化学分析方法 第3部分:硫量的测定 重量法和燃烧-滴定法
    China National Standards
    Y

    English PDF
    GB/T 3884.2-2012 Methods for chemical analYsis of copper concentrates - Part 2: Determination of gold and silver contents - Flame atomic absorption spectrmetric method and fire assay method
    铜精矿化学分析方法 第2部分:金和银量的测定 火焰原子吸收光谱法和火试金法
    China National Standards
    Y

    English PDF
    GB/T 3884.14-2012 Methods for chemical analYsis of copper concentrates - Part 14: Determination of gold and silver - Fire assay gravimetric and flame atomic absorption spectrometric method
    铜精矿化学分析方法 第14部分:金和银量测定 火试金重量法和原子吸收光谱法
    China National Standards
    Y

    English PDF
    GB/T 3884.13-2012 Methods for chemical analYsis of copper concentrates - Part 13: Determination of copper - Electrogravimetric method
    铜精矿化学分析方法 第13部分:铜量测定 电解法
    China National Standards
    Y

    English PDF
    GB/T 3884.1-2012 Methods for chemical analYsis of copper concentrates - Part 1: Determination of copper content - Iodine titration method
    铜精矿化学分析方法 第1部分:铜量的测定 碘量法
    China National Standards
    Y

    English PDF
    GB/T 3884.10-2012 Methods for chemical analYsis of copper concentrstes - Part 10: Determination of Antimony content - Hydride generation atomic fluorescence spectrometry method
    铜精矿化学分析方法 第10部分:锑量的测定 氢化物发生-原子荧光光谱法
    China National Standards
    Y

    English PDF
    GB/T 3880.3-2012 Wrought aluminium and aluminium alloY plates,sheets and strips for general engineering - Part 3: Tolerances on forms and dimensions
    一般工业用铝及铝合金板、带材 第3部分:尺寸偏差
    China National Standards
    Y

    English PDF
    GB/T 3880.2-2012 Wrought aluminium and aluminium alloY plates,sheets and strips for general engineering - Part 2: Mechanical properties
    一般工业用铝及铝合金板、带材 第2部分:力学性能
    China National Standards
    Y

    English PDF
    GB/T 3880.1-2012 Wrought aluminium and aluminium alloY plates,sheets and strips for general engineering - Part 1: Technical conditions of delivery
    一般工业用铝及铝合金板、带材 第1部分:一般要求
    China National Standards
    Y

    English PDF
    GB/T 3622-2012 Titanium and titanium alloY strip and foil
    钛及钛合金带、箔材
    China National Standards
    Y

    English PDF
    GB/T 3494-2012 Zinc oxide produced bY direct method
    直接法氧化锌
    China National Standards
    Y

    English PDF
    GB/T 3246.2-2012 Inspection method for structure of wrought aluminum and aluminum alloY products - Part 2: Inspection method for macrostructure
    变形铝及铝合金制品组织检验方法 第2部分:低倍组织检验方法
    China National Standards
    Y

    English PDF
    GB/T 29456-2012 EnergY management systems - Implementation guidance
    能源管理体系 实施指南
    China National Standards
    Y

    English PDF
    GB/T 29454-2012 Specification for equipping and managing of the measuring instrument of energY in the pulp and paper enterprise
    制浆造纸企业能源计量器具配备和管理要求
    China National Standards
    Y

    English PDF
    GB/T 29453-2012 Specification for equipping and managing of the measuring instrument of energY in coal enterprise
    煤炭企业能源计量器具配备和管理要求
    China National Standards
    Y

    English PDF
    GB/T 29452-2012 Specification for equipping and managing of the measuring instrument of energY in textile enterprise
    纺织企业能源计量器具配备和管理要求
    China National Standards
    Y

    English PDF
    GB/T 29416-2012 Test method for fire-resistant performance of external wall insulation sYstems applied to building facades
    建筑外墙外保温系统的防火性能试验方法
    China National Standards
    Y

    English PDF
    GB/T 29412-2012 Adsorber of pressure swing adsorption for hYdrogen purification
    变压吸附提纯氢用吸附器
    China National Standards
    Y

    English PDF
    GB/T 29411-2012 Technical specification of hYdrogen-oxygen generator with water electrolyte
    水电解氢氧发生器技术要求
    China National Standards
    Y

    English PDF
    GB/T 29363-2012 Water chiller with the vapor compression cYcle for nuclear power plant
    核电厂用蒸气压缩循环冷水机组
    China National Standards
    Y

    English PDF
    GB/T 29180.2-2012 The investigative methods and procedures for electrical fire - Part 2:Methods for dissolution and separation of phYsical evidence
    电气火灾勘验方法和程序 第2部分:物证的溶解分离提取方法
    China National Standards
    Y

    English PDF
    GB/T 29179-2012 Fire emergencY rescue - Code of practice for operation
    消防应急救援 作业规程
    China National Standards
    Y

    English PDF
    GB/T 29178-2012 Fire emergencY rescue - Guidelines for equipment allocation
    消防应急救援 装备配备指南
    China National Standards
    Y

    English PDF
    GB/T 29177-2012 Fire emergencY rescue - Requirements for training facilities
    消防应急救援 训练设施要求
    China National Standards
    Y

    English PDF
    GB/T 29176-2012 Fire emergencY rescue - General rules
    消防应急救援 通则
    China National Standards
    Y

    English PDF
    GB/T 29175-2012 Fire emergencY rescue - Guidelines for technical training
    消防应急救援 技术训练指南
    China National Standards
    Y

    English PDF
    GB/T 29174-2012 Thermal analYsis test method for constant-temperature stability of materials
    物质恒温稳定性的热分析试验方法
    China National Standards
    Y

    English PDF
    GB/T 29164-2012 Guide for utilization of certified reference materials for composition analYsis and physical property measurements of coal
    煤炭成分分析和物理特性测量标准物质应用导则
    China National Standards
    Y

    English PDF
    GB/T 29161-2012 Specifications of on-line analYzer for coal based on neutron activation analysis
    中子活化型煤炭在线分析仪
    China National Standards
    Y

    English PDF
    GB/T 29160-2012 Test methods for solar-plus-supplementarY water heating system (tank capacity more than 0.6m3)
    带辅助能源的太阳能热水系统(储水箱容积大于0.6m3)性能试验方法
    China National Standards
    Y

    English PDF
    GB/T 29158-2012 Technical code for solar-plus-supplementarY water heating system (tank capacity more than 0.6m3)
    带辅助能源的太阳能热水系统(储水箱容积大于0.6m3)技术规范
    China National Standards
    Y

    English PDF
    GB/T 29157-2012 Production life cYcle assessment specification for float glass(Product category rules)
    浮法玻璃生产生命周期评价技术规范(产品种类规则)
    China National Standards
    Y

    English PDF
    GB/T 29156-2012 Production life cYcle assessment specification for metal-plastic decorative panel(Product category rules)
    金属复合装饰板材生产生命周期评价技术规范(产品种类规则)
    China National Standards
    Y

    English PDF
    GB/T 29153-2012 Water reclamation and reuse facilitY
    中水再生利用装置
    China National Standards
    Y

    English PDF
    GB/T 29152-2012 Flue gas cleaning sYstem for municipal solid waste incineration
    垃圾焚烧尾气处理设备
    China National Standards
    Y

    English PDF
    GB/T 29149-2012 Requirements for equipping and managing of measuring instruments of energY and resource in public institutions
    公共机构能源资源计量器具配备和管理要求
    China National Standards
    Y

    English PDF
    GB/T 29148-2012 Technical code for energY saving of greenhouses
    温室节能技术通则
    China National Standards
    Y

    English PDF
    GB/T 29147-2012 MethodologY of the calculation of residuary heat resource during manufacturing of prepainted and galvanized steel
    钢铁生产余热资源计算方法 涂镀
    China National Standards
    Y

    English PDF
    GB/T 29094-2012 Temper designations for copper and copper alloYs
    铜及铜合金状态表示方法
    China National Standards
    Y

    English PDF
    GB/T 29093-2012 Seamless copper alloY tubes for subsurface sucker rod pumps
    地下杆式抽油泵用无缝铜合金管
    China National Standards
    Y

    English PDF
    GB/T 29092-2012 Magnesium and magnesium alloY terms and definitions of die-castings defects
    镁及镁合金压铸缺陷术语
    China National Standards
    Y

    English PDF
    GB/T 29091-2012 Copper and copper alloY designation and code system
    铜及铜合金牌号和代号表示方法
    China National Standards
    Y

    English PDF
    GB/T 29090-2012 Sampling method of batterY scraps
    电池废料的取样方法
    China National Standards
    Y

    English PDF
    GB/T 29088-2012 Corrosion of metals and alloYs - Electrochemical potentiokinetic reactivation measurement using the double loop method
    金属和合金的腐蚀 双环电化学动电位再活化测量方法
    China National Standards
    Y

    English PDF
    GB/T 29086-2012 Steel wire ropes - SafetY - Use and maintenance
    钢丝绳 安全 使用和维护
    China National Standards
    Y

    English PDF
    GB/T 29071-2012 Non-destructive testing - Test method for industrial computed tomographY (CT) examination of initiating explosive device
    无损检测 火工装置工业计算机层析成像(CT)检测方法
    China National Standards
    Y

    English PDF
    GB/T 29070-2012 Non-destructive testing - Industrial computed tomographY (CT) testing - General requirements
    无损检测 工业计算机层析成像(CT)检测 通用要求
    China National Standards
    Y

    English PDF
    GB/T 29069-2012 Non-destructive testing - Test method for measurement of industrial computed tomographY (CT) system performance
    无损检测 工业计算机层析成像(CT)系统性能测试方法
    China National Standards
    Y

    English PDF
    GB/T 29068-2012 Non-destructive testing - Guide for industrial computed tomographY (CT) system selection
    无损检测 工业计算机层析成像(CT)系统选型指南
    China National Standards
    Y

    English PDF

    Find out:32308Items   |  To Page of: First -Previous-Next -Last  | [161] [162] [163] [164] [165] [166] [167]

     

    +86-755-25831330        sales@gbstandards.org 
    106# Zhongmao Mansion,No.1 Beizhan Road,Shenzhen,China
    ©  RJS Copyright  2001-2024 All Rights Reserved

    - Since 2001 -
    Focus on China Standards & Compliance Services

    www.rjs.cn

    China Licenses

    www.transcustoms.com

    China HS code & Tariff

    www.gbstandards.org

    China National Standards