Ultra low profile integrated beckets.
Sheave - 2 5/32 in.
Max. Rope - 3/8 in.
Max. Cable - in
Pin - in.
M.W.L. - 1650 lb.
B. L. - 3300 lb.
Weight - 11.2 oz.
Product Information

Lightweight
Kilogram for kilogram of working load, BB and RT Orbit Blocks are the world's lightest. The unique orbital design allows the bearing to only be in the active areas of the floating sheave. This minimizes the mass of the inactive return race and hub.
Weight and bulk are further reduced in the different block configurations. The ball bearing single and becket block has a through-sheave becket arrangement. The result? The lowest weight possible.
Multi-sheave blocks have only single intermediate cheeks and an ultra-light and efficient head arrangement. This gives a 30% weight saving advantage over the nearest competitor. Other brands just link together their single blocks. This results in unnecessary double cheeks between each sheave, held together by a heavy steel channel across the top of the block.

Highest working load in its class
The orbital ball-bearing arrangement gives the largest possible bearing race diameter. This maximizes load performance. The proven Ronstan 2-stage bearing system features high compression grade acetal ball bearings and a secondary full-contact bearing. This gives minimum friction across the full working load range.
The floating sheave and bearing system is supported by a fiber-reinforced load frame. The design was computer modeled to be stress optimized. The DyneemaA Link is produced from FSE Robline SK75 fiber, which is 10 times stronger and lighter than steel, and provides the final connection from the block to the load point.
Holding power 20:1
Applications

Mainsheet systems on dinghies, sportsboats and small keelboats to 9m (30ft)

Spinnaker sheets on dinghies, sportsboats and small keel boats to 9m (30ft)

Halyard, Vang and Backstay application on boats to 8m (26ft)

Control line applications on larger yachts

Mainsheet systems and spinnaker sheets on dinghies, catamarans, sportsboats and small keel boats to 9m (30ft)

RF55410 when paired with a RF56330B and a RF35101 lashed to the becket produces a powerful 8:1 mainsheet system for use on catamarans to 5.5m

(18ft). This can be increased to 9:1 by replacing the RF35101 with a RF35202

Halyard, vang and backstay applications on boats to 8m (26ft)

Control line applications on larger yachts
Materials

Ball bearings - High compression strength carbon black Acetal

Stage 2 bearing - Carbon fiber reinforced, PTFE impregnated Nylon

Frame/Cheeks - Toughened, glass fiber reinforced Nylon