Ease that sheet smoothly out in the lightest air, and get an automatic ratchet block when it's a breeze on.
Shifting between ratchet and light-air modes is seamless. Harken 57mm Carbo Ratchamatic Single Block rolls freely in both directions under low loads and automatically engages the ratchet as loads increase. The 57mm load-sensing Carbo Ratchamatic® is adjustable for many applications and line loading conditions. With a 180-degree wrap, you get a 10:1 holding power. Commonly 57mm blocks are for jibsheets and spinnakers on small dinghies.
