The roller has a lubrication groove to disperse lubrication for a long time. Long life, low noise, cool temperature up to -45 degrees Celsius5. Reduce garage noise with precision ball bearings, and nylon wheels are much quieter than the original garage wheels. Applies to: Automatic garage door, vault garage door, solid wood garage door, anti-pinch garage door, mobile phone door Garage door, Designed garage door, Remote garage door, Villa garage door 11.5 x 4.5 cm / 4.53 x 1.77 inches (L x Diameter) Weight: 534 g Package Content: 4 x Garage Door Roller.