This 13-Piece kit is designed to fit many different wheel/axle combos, which is great for custom applications & custom wheels. Slightly oversized to fit 25mm OD Motorcycle Axles (Dimensions Below) (Dimensions ALL) ID: 25mm OD: 1-1/2” (One each of the following widths) 1/4", 3/8", 1/2", 5/8", 3/4", 7/8", 1", 1-1/8", 1-1/4", 1-3/8", 1-1/2", 1-3/4", 2" The wheel spacers are machined from 6061-T6 billet aluminum and feature a chamfered edge and come in an anodized gloss black finish. We also offer kits in a silver anodized finish.