ITEM ITSELF... all rolled well, bearings went very smoothly. The item fit the track (rollersize wise) and shaft diameter and length were correct. Garage door functions smoothly and well; in that these are a very good replacement for the ancient (20 plus years old) ones that came with the garage when I bought the place. If the dimensions listed match yours, then these are a good replacement. Normally one may not need all 12, hang onto any extras in case of future minor replacement.We have two garage doors and these would fit both so it seems they are a fairly standard size. I gave the product itself five stars because the rollers seem well made, fit well, and roll very well. IF my other garage door needs roller replacement, I would order these again.Only issue was packaging and shipping; there were two missing because it literally looked like someone compromised the flap sealing and reached in straight through the repackaging and into the original packaging and removed a handful. I left feedback. (I order a LOT through Prime and a lot of Warehouse deals, rarely do I have a problem. Almost always it's sing praises about fulfillment and shipping!)I needed 10, it said 12, and I did receive 10. I didn't have time to go through returns and replacement with my garage door defunct and unusable and weather about to turn. I installed them the day of receipt.