Carbo fiddle line features high-load ball bearings with fitted races for low-friction operation. The 57 mm fiddle features the Cam-Lock locking system. The patented switch allows the jaw to lock at 90-degree intervals, or to swivel freely. The 57 mm fiddle features the Cam-Lock locking system. The patented switch allows the jaw to lock at 90-degree intervals, or to swivel freely. The 57 mm switchable ratchets provide precise on/off control with accessible, easy-to-operate on/off switches on both sides of the block. Use for: Vangs, cunninghams, outhauls and mainsheet fine-tune.