The UR Premium conveyor roller is the Universal Roll standard. It is available in a 4, 5 and 6-inch diameter with 20, 25 and 30 mm shafts. It comes standard with 4 bearings per roll. These are grease-lubricated sealed bearings. A 6-baffle labyrinth filled with a specially formulated grease blocks dirt and moisture for complete sealing. The adjustment screw provides precision-adjusted labyrinths. Double-lipped seal available on request.