The Carbo Ratchets system enables sailors to hand-hold loaded lines while maintaining a balance between holding power and controlled easing. This 75mm Fiddle Ratchet Block Swivel with a Cam Cleat, Part No. 2696, features a 75mm sheave diameter (2 15/16 inches), maximum line diameter of 12mm (1/2 inch), and a maximum working load of 408kg (900lb).