Brand: SPA Design Racing Products
These tubing adapters are specifically designed to fit the SPA Billet Clamp-On Bottle Mounts, Part Nos. SP SPAT-Bxx (sold separately). They fit inside the tubing mount portion to adapt the 1 3/4" mount to your 1 1/2" OD tubing. Sold in 2 pairs (two complete rings, enough for two mounts).