Provides needle rollers running directly against a drawn cup outer race, giving high radial load capacity within a compact radial section. The open-end design (HK1210-B) has no inner ring, so the shaft surface itself must act as the raceway and needs to be hardened and ground accordingly. Outside diameter is 16.0 mm, width 10.0 mm, net mass 4.38 g. Limiting speed is 20700 1/min, with a reference speed of 15700 1/min. The bearing is supplied without sealing, so lubricant supply and contamination protection must be arranged externally, and grease or oil lubrication should be selected based on operating speed and temperature. As a needle roller bearing with a thin cross-section, it suits applications where radial space is limited but sufficient shaft hardness and dimensional accuracy at the raceway surface can be guaranteed.