Harken 2633 57mm Carbo Ratchamatic Cheek Block. 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.

• Sheave diameter:57mm
• Length: 83mm
• Weight: 89g
• Maximum line diameter:10mm
• Maximum working load: 227kg
• Breaking load: 907kg
• Holding power w/180 degree wrap: 10:1