PREMIUM NYLON MATERIAL - garage door rollers are made of high-quality nylon material and 6200ZZ bearings, which is sturdy and durable, more stable and quieter than metal rollers and other materials, and smoother than previous rollers, suitable for 2 inches garage doors. HIGH-LEVEL DESIGN - The stem of the nylon garage door roller has a galvanized coating to prevent rust. The design of the reinforced double-wall cage and the sealed 6200ZZ ball have the most powerful performance and super long service life. The garage door rollers can more than 10000 cycles under a load of 150 pounds. MORE STABLE AND QUIET -The 6200ZZ precision ball on the nylon garage door wheels rotates smoothly and the high-quality nylon material reduces noise greatly, which can reduce the noise of your garage door by 75%, ensuring your garage door runs smoothly and quietly. You can use it with . EASY TO INSTALL AND STANDARD SIZE - The garage door wheels are easy to install and replace. You can throw the , worn, noisy or damaged rollers and replace with quiet new garage door rollers. The actual diameter of the garage door roller is 1.81 inches and the thickness of the rollers is 1/2 inch, which fits the 2-inch track in most garages doors. Colour:White Material:Nylon + metal Size:120x46mm Package Contents: 12 * Nylon Garage Door Roller Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.