Material: 

Torque limiting portion: high-strength. hardened steel with rust protection (nitro-carburized)

a. Clamping hub D1: up to size 450, high strength alumunium; size 800 and up, steel

b. Clamping hub D2: up to size 60, high strength alumunium; size 150 and up, steel

Design: 

Two coupling hubs concentrically machined with concave driving jaws. One side wtih an integrated torque limiter. Available in single-position, multi-position, load holding, and full disengagement versions.