R4 Full Ceramic Ball Bearing, the inner diameter is 1/4", outer diameter is 5/8" and the width is 0.196", Bearing is made of Ceramic.

• Item: R4 Ball Bearings
• Type: Full Ceramic Ball Bearings
• Balls: ZrO2 Ceramic
• Cage: PTFE
• Inner/outer races: ZrO2 Ceramic
• Size: 1/4" x 5/8" x 0.196" inch
• Inner Diameter: 1/4" inch
• Outer Diameter: 5/8" inch
• Width: 0.196" inch
• Quantity: One Bearing
• Dynamic load rating: 335 LBS
• Static load rating: 139 LBS
• Highest Temperature: 356 (degrees fahrenheit) = 180 (degrees Celsius)