Carbo Ratchets allow sailors to hand-hold loaded lines and offer balance between holding power and controlled easing. Nylon resin side plates are densely packed with long-glass fibers for a compact block with a high strength-to-weight ratio. Machined aluminum sheaves are Hardkote anodized for strength and corrosion resistance. Eight facets hold line securely. Ball bearings sheave, and side plates are UV-stabilized with carbon black for maximum protection. The 75 mm switchable ratchets provide precise on/off control with accessible, easy-to-operate on/off switches on both sides of the block. For the ultimate system, mount a switchable ratchet in the cockpit and a boom-mounted Ratchamatic directly above for double holding power in heavy air and a free-running mainsheet when it's light. The 75 mm provides up to 15:1 holding power. Use for: Main/jib/spinnaker sheets, Mainsheet fine-tune, Traveler controls, Genoa leads and Fore guys.