You can purchase casters through Walmart either online or in stores. Stock will vary by stores, but if you go the online route, you are guaranteed to find a wider selection than in stores.
Rubber casters can be found at www.castercity.com. They care rubber and other material casters for your caster needs. They are low in price and shipping to your office.
Casters for furniture can be purchased from many companies on the internet. A few of the companies that sell Casters for furniture include eBay, Amazon, and Walmart.
Rubber casters are better for a hardwood floor as they will not scratch the wood surface and not leave black marks on your floor.
www.staples.com has office casters at really low prices. Check out your local Staples store for the casters of your choice. Casters come in made of different materials from nylon to rubber.
If your office chair has rubber chair casters, consider placing a plastic mat on the floor underneath your chair. This will protect your hardwood from any scuffing and will keep the casters from getting stuck in your carpet.
Rubber chair casters are better from others because the rubber adds traction, making it so that the chair doesn't slide all over the place while you are trying to work.
Rubber casters are found under furniture so that the furniture does not easily slide around. They may also stop the furniture from scratching up the floor.
Have an office chair that is leaving streaks all over the floor? Choose a chair with scuff-free rubber casters and save yourself time, energy and money.
Some great places where you can get soft rubber casters include CasterCity, ServiceCaster, eBay, Amazon, GreatLakeCaster. You might be able to also find some in your local shop.
Target has a moderate selection of rubber chair casters. http://www.target.com/Office-Star-Ergo-Drafting-Chair/dp/B000EMRPES Simply browse a bit to find what you are looking for.
The rubber casters are proper in unevend surfaces. In carpet floors, rubber wheel move hard and nylon wheel is better. In uneven tile floor rubber wheel is proper. But, if your tile floor is smooth, PU (polyurethane) wheel is good. You can see more information using following keyword searches and find corresponding web (you can use translate tools for reading). Aliam + Caster