The Safewaze 018-5007 unit�is lightweight with a durable translucent housing that not only looks unique, but protects the internal components from debris and contamination. The housing also makes for easy viewing and inspection of the webbing, reserve line, and pawl assembly. Class A: up to 24 in. if used above Dorsal D-ring. Class B: up to 54 in. if used up to a maximum of 2 ft below Dorsal D-ring