Carbo Ratchamatic® The Carbo Ratchmatic® is a load-sensing ratchet block that rolls freely in both directions under low loads, and automatically engages the ratchet as loads increase. Shifting between ratchet and light air modes is seamless. Unloaded main and jib sheets run out freely during mark roundings and asymmetrical spinnakers free instantly during jibes. Ratchet engagement may be adjusted to a higher or lower load according to strength and sailing style. The Ratchamatic® cheek block mounts on either port or starboard. Holding power of 57 mm is as high as 10:1. The 75 mm up to 15:1. For the ultimate system, mount a Ratchamatic® on the boom above a cockpit-mounted switchable ratchet to allow the mainsheet to run freely in light air, and ensure double holding power in heavy air. Use the 2634 with a 402 or 403 swivel arm for a versatile two speed mainsheet system. Use for: Main/Jib Sheets Asymmetric spinnakers