1. The precision ball bearing is fixed by impact in the steel housing, tight and durable.

2. Tight steel bearing unit could bear more axial force than plastic bearing unit.

3. Make it possible for the roller to work in the high or low temperature beyond the plastic part bearing (e.g. oven or cold storage).

4. Complete series of diameter, wid range of load capacity.

5. Compared with 1100 series with polymer bearing unit, its noise is a bit louder.