Ronstan RF35100 Series 30 Orbit Block Single Sheave Ball Bearing Swivel Shackle

The Ronstan RF35100 Series 30 Orbit Block is a lightweight, high-strength single sheave block designed for modern rigging systems on dinghies and sailboats. This 30mm block features a swivel shackle head and integrated becket, making it ideal for barber haulers, boom vangs, spinnaker sheets, backstay systems, halyard tuning, and Cunningham controls.

Advanced Two-Stage Bearing System:

• High compression acetal orbital ball bearings migrate to loaded areas for efficient handling of light to moderate loads
• PTFE-impregnated nylon bearing with carbon fiber reinforcement supports higher static loads
• Smooth operation throughout the entire load range with exceptional efficiency

Engineered for Performance:

• Glass fiber reinforced nylon cheeks and head provide exceptional strength-to-weight ratio
• Hollow bearing center serves as an integrated becket, reducing weight while adding versatility
• UV-resistant acetal sheave compatible with conventional double braid and high-tech 12-strand lines
• Swivel shackle head with 5/32" pin diameter for easy attachment
• Optimized for 5/16" (8mm) line diameter

Construction:

• Composite cheeks with glass fiber reinforcement
• Acetal sheave with high compression rating
• Carbon fiber reinforced bearing surfaces
• Stainless steel shackle pin

The RF35100 delivers the highest working load capacity in its class while maintaining minimal weight. The innovative design replaces unnecessary metal components with engineered composites, creating a compact block that excels in demanding marine environments. Whether used on racing dinghies or cruising yachts, this Orbit Block provides reliable performance for critical control line applications.