EXTRA LARGE WOODEN GRAND COASTERS - SET OF 3 - Polished Ebony

Inner Diameter: 3 1/8"
Outer Diameter: 5 5/8"
Thickness (center) 1/2" (Your piano will be raised by 1/2")
Thick Felt: Already installed.

 XX-Large Solid Wooden Caster Cups in polished ebony finish are the best choice for a Grand Piano with large wheels. The outer diameter is about 5.5" and the inside diameter is 3.125".