medical devices refer to instruments, equipment, appliances, in-vitro diagnostic reagents and calibrations, materials and other similar or related items directly or indirectly used in human body, including required computer software. Medical instruments include medical equipment and medical consumables. Utility is mainly obtained by physical means, not by pharmacology, immunology or metabolism, or it only plays an auxiliary role although these methods are involved. The purpose is to diagnose, prevent, monitor, treat or alleviate diseases; Diagnosis, monitoring, treatment, mitigation or functional compensation of injury; Inspection, substitution, adjustment or support of physiological structure or physiological process; Support or maintenance of life; Pregnancy control; Through the examination of samples from human body, information can be provided for medical or diagnostic purposes.