These Nylon Twin Wheel casters are perfect for light duty furniture. The stem is a 5/16-18 UNC x 1" Thread which allows for attachment to many types of furniture. Used primarily on carts, stands and some chairs. The nylon body construction provides for capacity at 75 lbs each, so these little casters can handle quite a load. The bodies are designed to take common abuse from office and shop enivronments.