Kuryakyn Universal Helmet Lock Street Racing Motorcycle Helmet Accessories - Chrome / 1-1/4"-1-1/2" Works on engine guards, frame tubes, or any other 7/8" to 1-1/2" tubes P/N: 4220 - Fitment: Universal Fitment for 7/8" to 1-1/4" Diameter Tube P/N: 4232 - Fitment: Universal Fitment for 1-1/4" to 1-1/2" Diameter Tube