Harken's Carbo Ratchamatic® Blocks are load-sensing blocks that roll freely in both directions under low loads and automatically engage the ratchet as loads increase, making shifting between ratchet and light-air modes 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 75mm Ratchamatic® provides up to a 15:1 holding power. 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 to double holding power in heavy air.
The patented switch locks shackle in front or side positions, or lets block swivel to keep line from twisting. The eight-faceted, hard lube-anodizing aluminum sheave holds line securely.
|Sheave Diameter||2 15/16 in||75 mm|
|Max Line Diameter||7/16 in||12 mm|
|Max Working Load*||300 lb||136 kg|
|Breaking Load*||750 lb||340 kg|
|Holding Power w/ 180° Wrap||15:1||15:1|
|Shackle Pin Diameter||1/4 in||6 mm|
|Weight w/ Shackle||15.5 oz||440 g|
|Length||5 7/16 in||138 mm|
*MAXIMUM WORKING LOADS AND BREAKING LOADS FOR BLOCKS BASED ON CAM STRENGTHS