This solid stainless steel spanner bushing is the most popular bushing in the industry which is typically used in most all 2" Wide Stainless Steel Casters and Wheels in which use a 3/4" OD Roller Bearing. This Stainless Spanner bushing is meant to reduce the outer diameter of a roller bearing from 3/4" OD to 1/2" ID which allows a 1/2" Axle Bolt to fit perfectly.