Needle Roller Bearing Bearing Industry Number 55 Bearing Design J Bore Diameter 5/16 in Cage Material Steel Closure Open Full Complement No Lubricant Material Grease Oil Maximum Speed 18 000 RPM Grease 28 000 RPM Oil Maximum Temperature 250 Degrees F Minimum Temperature -5 Degrees F Needle Bearing Type Drawn Cup Needle Roller Bearing Number of Rows One Outside Diameter 1/2 in Overall Width 0.313 in Ring Material Alloy Steel Roller Material Alloy Steel Seal Type Not Applicable