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Binks is your stop for all boating and watersport needs
Binks is your stop for all boating and watersport needs

Ronstan S55 RT Orbit Block,Cheek Anti-Clockwise Rotatio (RF56151

by Ronstan
Original price $106.05 - Original price $106.05
Original price
$106.05 - $106.05
Current price $106.05
SKU RF56151A

Awesome ratchet block holding power
Quite simply, Ronstan Ratchet Orbit Blocks ’?½ have the highest holding power available. The sophisticated NC-machined sheave features Generation 2 of our patented sheave cross-hole geometry. Its holding power is up to 14:1, double that of competitors.

The unique sheave design has 12 gripping faces which directly resist loaded line movement. Traditional designs have only 8 faces with an angled resistance to line movement. The Generation 2 design has straight resistance faces which both distribute the load and minimize rope wear. These faces are offset from the radial line, to draw the rope down into the gripping area when under load.


  • Auto and Manual ratchet in one block
  • Up to 14:1 holding power - highest available!
  • Smooth easing of sheets
  • Anti - Clockwise rotation
  • Recessed underside to suit curved mounting surface
  • Low mounting points for maximum strength


  • Dinghy mainsheet systems
  • Mainsheet fine tune systems on sportsboats & small keel boats
  • Mainsheet systems on sportsboats using RF7 mainsheet swivel cleat unit
  • Spinnaker and job sheets on dinghies - especially modern asymmetric classes
  • Control line applications on larger yachts

Sheave ? 55 mm
Max. Rope ? 10 mm
Pin ? - mm
M.W.L. 250 kg
B. L. 700 kg
Weight 76 g