Ronstan Series 55 Orbit Block - 55 mm (2 5/32") - RF55171

The Ronstan 55 mm Series 55 Single Orbit Block™ with Upright Lead (RF55171) boasts the highest strength-to-weight ratio available. This is achieved through all-composite reinforced polymer materials and a Dyneema® rope link head. Their precision design allows the optimum number of ball bearings in loaded areas and eliminates them in inactive areas. Ineffective mass is reduced even further through fiber-reinforced composites in the block head, cleat arms and beckets.

Features:

• Ultra Lightweight
• Low friction 2-stage Orbital ball bearing system
• Highest working load in its class
• Low profile and compact
• High performance cleating
• Easily fitted and securely retained Dyneema Link head

Applications:

• Mainsheet systems on dinghies, sportsboats and small keelboats to 9 m (30')
• Spinnaker sheets on dinghies, sportsboats and small keel boats to 9 m (30')
• Halyard, Vang and Backstay application on boats to 8 m (26')
• Control line applications on larger yachts
• Mainsheet systems and spinnaker sheets on dinghies, catamarans, sportsboats and small keel boats to 9 m (30')

Specifications:

• Safe working load: 1100 lb (500 kg)
• Breaking load: 2200 lb (1000 kg)
• Sheave diameter: 2 5/32" (55 mm)
• Maximum line size: 3/8" (10 mm)
• 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
  • Rope Link: UV stabilized, multi-strand impregmented SK75 Dyneema®