4" x 1-1/4" Swivel Wheel Casters with 2" Expand Thread Stem Caster This caster is perfect for material handling in any business or industrial setting. The 4" x 1-1/4" swivel wheel caster come with a 2" expand thread stem and brake for added security. The stem length is 2-1/2 inches with a stem diameter of 3/8 inch. The shank is 1 inch in length with a thread length of 1-1/2 inches and a stem expand length of 2 inches. This unit type is a single unit and the country/region of manufacture is unknown. Thanks for stopping. Please visit my slow growing store, read about me, my policies and view other items that may interest you. Also, check out my other casters wheels. **I always have money saving volume discounts on most items** David - thediscountretailer