The Avenger C461-1 LP Eye Coupler grid clamp comes supplied with a 28 mm(1 1/8\") male TV spigot. Commonly referred to as a Big Ben Clamp this popular clamp is ideal for many rigging systems, truss and entertainment configurations. TÜV and SÜD certified, you can feel confident that this cheeseboro clamp with junior pin will perform in any demanding environment. The LP Eye Coupler uses a wing nut with washer locking design and is able to clamp down on round tubes, truss or grids ranging from 48 mm(1.9\") to 52 mm(2.04\") and is 50 mm(1.96\") wide. Capable of holding up to 220 kg/484 lb loads this clamp will perform in many demanding environments. Recommended Accessories: E390, C155, C460-1, C463-1, C4460-1, C464-1, E200, C4465-1,