Extra Large Chair Wheels. 4" Set of Five. Great for carpet. Replaces chair mat.

Edit May 2022:Bought these and chair again in August '13 after a long-distance move, and both still going strong—so they definitely deserve 5 stars for longevity under a big heavy guy!Edit July 2013:These casters are still working perfectly on the Ravino chair nearly two years later. I am now ahead financially, having saved on two mat replacements, and that looks set to continue. Perfect rolling action, zero problems--this is a top-class product.I was ready to change my rating to five stars if the seller had updated their FAQ page to address the issues expressed here over the years. But no, they haven't--so I haven't. Great product let down by inattentive seller.Original review September 2011:Installed these yesterday after my chair mat almost succeeded in stabbing me with another broken shard of hard plastic. Fine casters so far, moving well on standard office carpet.I deducted a star after experiencing installation problems, and not finding a scrap of help on the seller's website. Seller, you already have a questions page, I recommend you include answers to some of the questions or issues raised in these reviews.First caster installed fine with strong hand pressure--as did the fourth, later. Second didn't, but eventually went in with some light tapping from a small hammer. However, this didn't work with the third [or fifth] caster, and I wasn't about to start any serious hammering. I tried different casters on different chair legs, in case it might be an issue of two maximum machining tolerances causing a failure.Getting the first two casters in suggested it wasn't the main caster stem which was the issue, and led me to quickly identify the problem as badly shaped metal rings in the groove at the head of the caster stem--they were jutting out too far beyond the diamater of the stem. They are very strong rings, I couldn't squeeze them smaller with a needle-nose pliers.I went with the easier solution of prying off the problem rings, and then using the rings from the old casters in their place. These other rings were a little more flexible, I was able to shape them with the pliers both to open [to get them on the stem] and finally close them a little. Miracle Casters popped in fine after doing this.The function of the rings seems to be to hold the casters in the chair leg, without one the caster was totally free to slide on and off the leg. I'm only guessing that you could use the casters just fine without the rings, but they'd fall off if you lifted the chair--not too big an occasional deal for most people, probably.Fyi, I'm using these casters with  Alera Ravino Big & Tall Series High-Back Swivel/Tilt Leather Chair, Black , they might be overkill with smaller less sturdy chairs, especially ones without metal legs.

These are everything claimed, Worth the price even with shipping to NZThese work supurbly on my desk rug on carpet. They're very gentle on both with their large surface area, roll easily and raise the chair base nicely offering lots of clearence for my old hanging out the bottom cylinder which was previously catching on the rugPurchased to replace office oasis blade, which were purchased to replace stock Aeron carpet castors. The blade style castors helped things one way by lifting the base, but crushed, and mangled the rug badly due to their small contact surface area. The Miracle castors are really comfortable, and feel very solid so far. They are biigg and make the chair somehow look more imposing.. but I like that too

Castors are big and sturdy. They were easy to install and do make my chair easier to roll on carpet. The only thing I do not like is that I sit a little to high now even on the chair’s lowest setting because I am only 5’3.

I have tried so many types of mats at various times over the years to roll properly on the carpets as I've moved into new places. Nothing worked well. I do not like to feel like I'm sliding around on glass - I like a bit of resistance when I'm in my office chair. That feeling of being in the office on business carpet tiles over concrete is perfect to lean, and shift, and roll, but it's a white whale on home carpeting. The Miracle Casters are what I've needed this entire time. I considered other types of replacement wheels for my chair, but these tall and wide wheels provide a great movement on carpet that I imagine, due to surface area, couldn't happen with any of the other options. I'm a big guy, but my chair base is metal, so I'm not worried about the base cracking other reviews mention. With that said, I can definitely feel the pressure on the spokes as I push around, so if you have a plastic base I could see that being a concern to consider. These are 100% worth the cost.

these are actually good. they roll easily and change direction quite easily on my carpet.these are the third set of casters I have tried to be able to move my chair on the carpet.third time is the charm!!!

I needed to raise my chair a bit to be in a better position at my desk. These work great. I just had to pop my old wheels out and pop these in, and that was it.

I was looking for a way to raise the height of my office chair to better work with my desk. This was the perfect fix. Incredibly easy to install. They move like a dream. I was worried about the cost but as of right now they are worth every penny!!

After trying some roller blade wheels that failed I decided to try these.1st, they make the chair taller. Noticable taller. That was nice as at max height i still found my chair a bit low for my desk.2nd, they definately roll better on my carpet than the stock and the roller blade casters. By far.3rd, makes my chair look like it's ready to go offroading!

What an upgrade / improvement. Expensive. But highly recommended.

The old wheels on my Aeron were dying, and I moved to a place where my chair was on a medium depth carpet, and I was basically immobile.I did some research and found out that those rollerblade-style wheels that are extremely popular and prevalent aren't necessarily super good on carpet, so I took a chance on these.10/10, would recommend. Definitely what you're looking for with carpeted floors.I've seen the reviews saying that the larger wheels may strain the base of the chair. This is not a problem on the Aeron, which has a metal base.

These are great, much better quality than the smaller wheels that originally come with your chair.And they extend the height of your chair at least 2 inches.

Work pretty good on carpet.