... Two types: 1, Metal stamping(TLA, TA, TLA=HK) 2, Steel plat(NA, TAF, TAF=NK) Precision ... :Two types:1, Metal stamping(TLA, TA, TLA=HK)2, Steel plat(NA, TAF, TAF=NK). ISO ... Bearing radial running clearance conforms to the value defined by 0 group of GB/T4604..Special precision grade ... disposition design of bearings, refer to the relevant recommendation in the applied technology of rolling bearings.TLA...Z ...