Swivellink Conveyor Bearing Blocks attach to the extrusion body and holds the bearing used for the rollers on the conveyor. Blocks includes the bearing, T nut, and fasteners. The bearing fits the 1/2" diameter shaft of the rollers. Conveyor Bearing Blocks are Designed for easy bearing replacement when needed. The block has a boss to position and guide the block onto the extrusion fastener slot.