WHICH BLOCK FOR MY BOAT ? Depending on the navigation programme. Block model small catamaran cruising boat, WHICH TECHNOLOGY ? Example : Bearings in ball blocks can distort if left under static load for long periods. In such a situation, the choice of a plain bearing block is recommended. flements given here are only Ball bearing blocks All load bearing parts are of 316 stainless steel. A : Heavy duty forged stainless bar shackle. B : Solid stainless trunion type swivel assembly. C : Stainless steel internal side plates. D : Sheave is moulded from Acetal resin. E : Delrin ball bearings. F : Side plates are precision moulded from glass impregnated nylon. G: Block is through bolted and spin rivetted Single, double, triple, snatch, fiddle, stand-up, cheek, stanchion... Plastimo offers a comprehensive selection of blocks.