Harken 57mm Carbo Fiddle Ratchet Block with Becket and Cam allows for 3:1 or 4:1 tackles on dinghy vangs and mainsheets.

Carbo fiddle Ratchet blocks allow sailors to hand-hold loaded lines and offer balance between holding power and controlled easing. Lightweight Carbo Ratchets are available in 40mm, 57mm and 75mm sizes. All the Carbo Ratchets feature a recessed On-Off switch that is easily operated from either side. The 40mm cam-arm versions work in ratchet mode only. Commonly 57mm fiddle blocks are for jibsheets and vangs on small dinghies.  

The 40mm, 57mm and 75mm Carbo Ratchamatic® is adjustable for many applications and weather conditions. The load-sensing ratchet block rolls freely in both directions under low loads, then engages the ratchet automatically as loads increase. With 180 degree wrap, you get a 10:1 holding power. 

• Many configurations to fit jibsheets, spinnakers and mainsheet systems
• Hand-hold your loaded lines
• Use for vang systems on dinghies, sportsboats, and medium keelboats
• Ratchet fiddle blocks are hand and crew savers
• Allows a line to be eased instantly with control
• On/Off switch allows the ratchet to be turned off in light air
• Hardkote-anodized aluminum sheaves
• Stainless steel swivel shackle
• Sheave Diameter: 2 1/4" (57 mm)
• Max. Line Diameter: 3/8" (10 mm)
• Max. Working Load (MWL): 792 lb. (359 kg)
• Breaking Load: 2380 lb. (1080 kg)
• Weight: 10.7 oz. (303 g)
• Length: 5 5/8" (143 mm)