Needle Roller Bearing 1. Material: Chrome steel 2. Type: A. Drawn Cup Needle Roller Bearing Bearing NO.: HK, BK, HK...2RS, HK...RS, BK...RS, FFH, MF, MFH, FY, MFY, etc. It is for a thin outer ring of needle roller bearing stamping molding. Its main characteristic is a low sectional height and higher load capacity. It is mainly used in bearing configuration with compact structure and inexpensive price and inside hole of bearing case could not be used as needle roller cage assembly.