Power3 ratchet blocks provide sailors that race small one-designs with three holding-power options to handle a variety of wind and sea conditions. More choices allow sailors to fine-tune their set-ups in tandem with the purchase that provides the ideal level of power, responsiveness and grip. The Carbo Ratchamatic® 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. 2x grip: big breeze/steady: 20:1 holding power. Length (mm) 103 mm Length (in) 4 1/16 in Weight (g) 104 g Weight (oz) 3.7 oz Maximum working load (kg) 227 kg Maximum working load (lb) 500 lb Breaking load (kg) 907 kg Breaking load (lb) 2000 lb Sheave Ø (mm) 57 mm Sheave Ø (in) 2 1/4 in Maximum line Ø (mm) 10 mm Maximum line Ø (in) 3/8 in Shackle pin Ø (mm) 5 mm Shackle pin Ø (in) 3/16 in Holding power 20:1