The Mongoose Cable Pulley was designed to provide a secure running belay on ropes challenge course cable.  It features a case hardened steel sheave heat treated .030 deep to a rockwell C scale of 56-58.  We choose this temper to prevent the steel sheave from becomming brittle....by case hardening the wheel we impart wear on the wheel after the heat treat wears down and not on the main life support ropes course cable.  The axles and side body plates are 304 stainless steel.  The sheave has an oilite bushing which gives exceptional performance in the outdoor challenge course environment.  For safety reasond the Mongoose has a wall thickness of .180 around the clip-in hole and .090 around the back-up bolt for unprecedented strength characteristic. The scissor action makes for quick installation on cable up to 1/2".  When used with the Stargate Spin Static the belayer is positioned 90 degrees to the belay cable for safety and control.