PREMIUM NYLON MATERIAL - Our garage door rollers are made of high-quality nylon material and 6200ZZ bearings, which are sturdy and durable, more stable and quieter than metal rollers and other materials, and smoother than previous rollers, very suitable for 2-inch 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 bearing cage and the sealed 6200ZZ ball bearing provides excellent performance and a super long service life. The garage door rollers can last over 10,000 cycles under a load of 150 pounds. MORE STABLE AND QUIET - The 6200ZZ ball bearing on the nylon garage door wheels rotates smoothly and the high-quality nylon material greatly reduces noise, which can reduce the noise of your garage door by 75%, ensuring your garage door operates smoothly and quietly. EASY TO INSTALL AND STANDARD SIZE - The garage door wheels are easy to install and replace. You can remove the old, worn, noisy, or damaged rollers and replace them with our quiet new garage door rollers. The actual diameter of the garage door roller is 1.81 inches and the thickness is 1/2 inch, which fits the 2-inch track in garage doors. Color: White Material: Nylon + metal Size: 120x46mm Package Contents: 12 x Nylon Garage Door Rollers Only the above package content is included; other products are not included. Note: Light and different displays may cause the color of the item to vary slightly from the real thing. The measurement allowed error is +/- 1-3cm.