The MPD allows you to go from lowering to raising without changing hardware. More than nine years of research and development went into the patented Multi-Purpose Device (MPD), which features major innovations in advanced technical hardware for rope rescue professionals. The MPD’s high-efficiency pulley, with an integral rope-grab mechanism, allows it to be used as a lowering device on the main line and belay line systems and be quickly changed over to a raising system without switching out or replacing hardware.