Stage Right by Monoprice O-Clamp Old C-clamps are a very easy way to mount lighting fixtures. However, soft aluminum gets scratched very quickly and can look less than great at events and weddings. Whether you are using a 12-20 inch touring truss or a 6-8 inch display truss, these Stage Right O-clamps are ideal. Fitted inserts (included) allow you to use 1-, 1.5-, or 2-inch trusses with style and ease. Made of high-impact molded ABS, these clamps look good, can support up to 75 pound fixtures, and will not scratch bars. The low-profile design makes getting your lights into tight places a breeze. It is especially useful when used with truss warmers. It features a 10M light mounting screw with wingnut for use with our 612733 Truss Wash Uplight.