Our Carbo Violin range has heavy-duty ball bearings, smooth-running in round shells. The 40mm violin block is ideal for 3:1 and 4:1 tackles, on dinghy downhauls and mainsheets, but also for control lines such as cunningham and internal boom outhauls on larger yachts. The 57mm violin block has the Cam-Lock device, which allows the arm to be locked in 90 degree increments or rotated freely. Carbo Ratchets These reversible ratchets are precision on/off with easy to reach and operate switches either side of the block. Use: Downhaul Cunningham foot stretcher Fine trim on mainsheet