How Is GKZ Classified?
Counter, Differential Cell is FDA product code GKZ, Class 2, 21 CFR 864.5220.
What Does It Take to Sell It in the United States?
A 510(k) premarket notification is required before it is sold in the United States: the applicant shows the device is substantially equivalent to one already on the market. Chinese applicants hold 2 clearances under this code; the FDA took a median of 235 days from receipt to decision on them.
What Has Gone Wrong With It?
The FDA has recorded 244 recalls under this product code since 2002. None was by a company in China. 5 are Class I, the most serious grade.
The root causes the FDA records most often are Software design (55), Nonconforming Material/Component (15) and Device Design (13). A recall is a fact about one product and its maker, not a grade for every manufacturer of the type.