WHAT YOU GET: You will receive 12 nylon garage door rollers; The quantity is sufficient to meet daily needs and replacements, the garage door rollers are sized to fit most residential garage doors. Smooth and quiet: Our garage door rollers are made of quality nylon and 6200ZZ bearings, smooth and high load, strong and reliable, quality nylon material reduces noise, ensuring your garage door runs smoothly and quietly. Sealed garage door rollers: the roller nylon opener for the garage door is designed with reinforced double-walled bearing covers, the bearing covers provide extra protection against dust and dirt, moisture from entering the bearings; Effectively extends the product's lifespan. Fits the size: Our black replacement garage rollers are 4.8 inches in diameter for 2-inch tracks and 4.7 inches long shaft; The correct size makes the rollers run smoother on the track and fits most residential garage doors. Easy to install: the black garage door wheels are easy to install and replace, with just one tool. It's easy to remove the old, worn, and noisy rollers from yours and replace them with our new rollers, and you'll have a quiet environment. Color: as shown. Material: nylon. Size: 30.30x21.79x5.21 cm. Package contents: 12 * Rollers. Only the above package content, other products are not included. Note: Light reflections and different displays may cause the color of the product to differ slightly from the real item. The allowed measurement error is +/- 1-3 cm.