Needle Roller Bearing Bearing Industry Number 57 Bearing Design B Bore Diameter 5/16 in Cage Material Not Applicable Closure Open Full Complement Yes Lubricant Material Oil Maximum Speed 8 300 RPM Maximum Temperature 248 Degrees F Minimum Temperature -22 Degrees F Needle Bearing Type Drawn Cup Needle Roller Bearing Number of Rows One Outside Diameter 1/2 in Overall Width 0.438 in Ring Material Alloy Steel Roller Material Alloy Steel Seal Type Not Applicable