● Applicable to medium and heavy loads. Waterproof design. ● The shaft uses alloy stell and hardened through vacuum heat treatment to HRC60˚±2˚. ● The center uses the combination of taper roller bearing, thrust bearing and needle bearing. NCR-MT3A NCR-MT4A NCR-MT5A NCR-MT6A NCR-MT3B NCR-MT4B NCR-MT5B