This standard specifies the terms and definitions, composition, basic requirements, technical requirements, test methods, inspection rules, identification, labels, instructions for use, assembly and packaging, transportation, storage and quality commitment requirements of cystatin C determination reagents (kits). . This standard is applicable to fully automatic biochemical analyzers, reagents (boxes) for the quantitative determination of cystatin C (also known as cystatin C, CYS-C, etc.) in human samples based on immunoturbidimetry.