Outwaters Black Non-Hooded Diecast wheels are heavy duty. Made of a combination of metals including Zinc, Copper, Aluminum, Magnesium, Pewter and Tin provides superior rigidity to wheels lacking the diecast based alloys. Outperforming and outlasting other wheels on the market and supporting up to 110lbs per wheel without cracking or warping assures that these wheels are in fact better for use under furniture even when you are moving it around. With nylon wheels moving in opposite directions any snagging on carpets is eliminated, making them a better choice for replacement wheels on your furniture in your home or office. These superb heavier duty twin wheel caster for chairs, tables, plant stands, ottomans, furniture and light equipment can also be used on medical equipment, IV stands, computer stands, a/v stands and display units. With easy mounting options available these non-marring wheels are ideal for ALL floor surfaces, including hardwood floors and tile/marble floors.