V-Belt Idler Pulley Bearing Type Ball For Belt Type Flat Bore Diameter 17 mm Face Width 0.77 in Outside Diameter 3.5 in Pulley Material Fiberglass-Reinforced Nylon Bearing Closure Double Sealed Bearing Material Chrome Steel Bearing Number 6203-2RS Face Diameter 3 in Face Type Crowned Features ABEC-1 Bearing For Belt Series Powermax For Use With Self Adjusting Belt Tensioner Lubrication Mobil Polyrex EM Material Fabrication Molded Maximum Operating Temperature 350 Degrees F