HexrackII clamps get a rock solid grip on the rails with a synthetic sleeve that fits between the clamp and the rail.
The cross clamp is used to connect two hexagonal tubes at 90-degree angles (for example, to connect a leg tube with a tube that has been horizontally set).
With a synthetic sleeve, HexRackII clamps get a rock solid grip on the rails. As the clamp tightens, it compresses the sleeve to establish a solid grip. This gives the clamp a secure, slip-free hold on the rail when tightened, and allows easy adjustment when loosened, making the whole setup process quick, easy, flexible and solid.