The CRS-1 is a professional tool set for installation of crown races onto forks with 1' and 1 1/8' steering columns. Using the long strong driver tube one of the included drifts and a hammer or mallet not included the CRS-1 safely and accurately drives the crown race into its properly seated position. Includes six specially-sized drifts — three in the 1' standard three in the 1 1/8' standard — for compatibility with most crown race shapes and designs. Each drift is made from anodized aluminum to avoid damaging the crown race. Compatibility: Steering columns with a 1' or 1 1/8' 25.4 to 28.6 mm diameter SHIS sizes 26 27 and 30 Steering columns up to 340 mm in length NOTE: Steering column diameter as it pertains to crown race setting is measured at the base of the steering column. For oversized 1 1/4' or 1 1/2' columns use the CRS-15.2 Crown Race Setter.