"This Fairbanks Phenolic/Canvas Swivel Caster is ideal for applications where smooth, quiet and mobile operation is required. Wheel Diameter in. 4, Bearing Type Roller bearing, Capacity lbs. 300, Post in. 1/2-13 x 1, Material Type Phenolic/canvas, Casters qty. 1, Wheel Width in. 1.25, Overall Height in. 5, Wheel Type Phenolic canvas, Finish Type Zinc-plated, Caster Type Swivel. Durable construction and cold-formed Rust-resistant electro-galvanized zinc finish Phenolic/canvas wheel Stem dimensions 1/2 in. dia. x 1 in. L, 13 threads per in."