Ronstan Series 75 Bottom Block for RF72700B Twinspeed SystemCoarse and and fine tuning purchase system
Unrivaled 18:1 holding power
Dual sided On-Off switch
Low friction ball bearing system
Cheek cut-outs for easy bearing maintenance
Sheave Ø - 3 + 2 in.
Max. Rope Ø - 3/8 in.
Max. Cable Ø - in
Pin Ø - in.
M.W.L. - 1760 lb.
B. L. - 3750 lb.
Weight - 30.2 oz.
Two-speed mainsheet systems allow both coarse and fine tuning in a single purchase system. The system allows fine tuning of the mainsheet when sailing upwind by using one of the sheet tails and keeping the other cleated. Using both the sheets at once allows the trimmer to blow off the main quickly when rounding the top mark and trim on quickly when hardening up after rounding the bottom mark. When fitting to traveler cars, ensure adequate support for the bottom block and use stand-up spring kit RF324-1 or RF324-2.
Mainsheets on sportsboats and keel boats to 12m (40ft)
Mainsheets on sportsboats and keelboats to 12m (40')
Max. mainsail area, END boom sheeting = 38sq m (409 sq ft)
Max. mainsail area, MID boom sheeting = 23sq m (248 sq ft)
Carbon Black Acetal ball bearings
U.V. stabilized Acetal sheaves, alloy ratchet sheaves
Torlon® ratchet pawl
Adjustable cleat arms