The centerpiece of this easy-to-install system is the innovative 2141 claw hook clamp that securely grabs both sides of any DW or PDP bass drum counter hoop. A height-adjustable hi-hat arm includes a 9213 incremental hi-hat cluch which allows drummers quick, variable tension adjustment of hi-hat cymbals, stack effects and other hi-hat mountable percussion accessories. Designed to work with 18"-24" diameter bass drums. Always attach the rubber foot on the bottom of the rod, to reduce the risk of scratching your bass drum surface while using this product.