Mast block, sheave 40, 11 different sizes with diameters from 40 to 120 mm for working loads (SWL) up to 7000 kg. Anodized aluminum frame with insulating washers for corrosion protection. Resin sheaves (aluminum sheaves for 100 and 120 mm only) with composite fibre main bearing (not on size 40) and double side self-captive ball bearing.