PREMIUM NYLON MATERIAL to Our garage door rollers are made of hightoquality 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, very suitable for 2 inches garage doors.HIGHtoLEVEL DESIGN to The stem of the nylon garage door has a galvanized coating to prevent rust. The design of the reinforced doubletowall bearing cage and the sealed 6200ZZ ball bearing make it have the 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 toThe 6200ZZ ball bearing on the nylon garage door wheels rotates smoothly and the hightoquality nylon material reduces noise greatly, which can reduce the noise of your garage door by 75 percent , ensuring your garage door runs smoothly and quietly. You can it with .EASY TO INSTALL AND STANDARD SIZE to The garage door wheels are easy to install and replace. You can throw the old, worn, noisy or damaged rollers and replace with our quiet new garage door rollers. The actual diameter of the garage door is 1.81 inches and the thickness of the rollers is 1 or 2 inch, which fits the 2toinch track in garages doors.Colour:WhiteMaterial:Nylon and metalSize:120x46mmPackage Contents:12 x Nylon Garage Door Only the above package content, other products are not included.Note: Light and different displays may the color of the item in the a little different from the real thing. The measurement allowed error is 1to3cm.