Ronstan RF41200 Series 40 AP Double Block Swivel Head Marine Pulley

The Ronstan RF41200 Series 40 All Purpose Block is a high-performance double sheave block with full swivel head design, engineered for demanding marine applications on sailboats up to 26 feet. Self-lubricating Acetal polymer sheaves run on polished stainless steel races to deliver reliable performance under both dynamic and high static loads, making this block ideal for sheets, halyards, and control line applications in cruising and racing environments.

Key Features:

• Double sheave configuration with freely swiveling head for optimal load alignment
• Exceptionally high working load of 600kg (1,320 lbs) with 1,200kg (2,650 lbs) breaking strength
• Self-lubricating sheaves for low maintenance and extended service life
• Slotted pin shackle design prevents line fouling
• Two-way head post construction for versatile attachment options

Construction and Materials:

• UV-stabilized Acetal sheaves resist sun damage and degradation
• Impact and UV-resistant fiber-reinforced Nylon cheeks
• Grade 316 stainless steel bearing race for corrosion resistance
• Grade 316 stainless steel load strap and head fitting

Applications:

• Mainsheet systems
• Halyard control
• Boom vang
• Spinnaker control lines on off-the-beach catamarans, one-design classes, and sportsboats

Specifications:

• Sheave Diameter: 40mm (1-9/16")
• Maximum Rope Diameter: 10mm (7/16")
• Pin Diameter: 5mm (3/16")
• Maximum Working Load: 600kg (1,320 lbs)
• Breaking Load: 1,200kg (2,650 lbs)
• Weight: 135g (4.8 oz)