The Organic block is an original concept that combines composite cheeks with aluminium axle, Delrin sheave and balls. 
This gives near zero friction and heat resistance allowing maximum performance in racers up to 32ft. This version has a switchable on/off ratchet.

Working load - 240kg
Breaking load - 500kg
Rope Diameter - 5-12mm
Sheave diameter - 57mm
Weight - 107g