Bearing Type: 6200ZZ<br> Wheel Material: Nylon <br>Single Load: 150 Lbs<br> Wheel Thickness: 1/2" <br>Wheel Diameter: 1-13/16" <br>Total Length: 4-3/4" <br>Shaft Length: 4"<br> Shaft Diameter: 7/16" <br>Temperature Range: -30 ~ 100 Degrees Celsius <br>Package include: <br>12 x 6200ZZ Garage Door Rollers