This is the latest trend in an extruded aluminum Half Coupler, aka Cheeseborough. It's designed for quick and safe mounting of stage lighting fixtures to lighting truss and lampbars. Couplers don't dent, or dimple your expensive lighting truss like a C-clamp. Fastens securely to both 1.5" schedule 40 black pipe and 2" O.D. aluminum tubing and features a narrower width (1.25") for hanging items closer together. Lab Certified to a 600lb working load.
S&H from $5.99 in continental US (e-mail for international rates)