Ronstan Series 40 All Purpose Double Block, Swivel Head, 40mm Sheave

Optimize your rigging performance with the Ronstan Series 40 All Purpose Double Block. Engineered for both dynamic and high static loads, this versatile block features self-lubricating Acetal polymer sheaves running on polished Grade 316 stainless steel races, ensuring smooth, low-friction operation and exceptional longevity. Its robust construction includes UV-stabilized Acetal sheaves and fiber-reinforced Nylon cheeks, providing superior durability and resistance to harsh marine environments. The freely swiveling head and slotted pin shackle prevent fouled lines, making it an ideal choice for a wide range of sailing applications. Upgrade your sailboat's control systems with Ronstan's trusted reliability.

Key Benefits & Specifications:

• Versatile Performance: Features a 40mm (1-9/16") sheave diameter and accommodates ropes up to 10mm (7/16"), suitable for diverse rigging setups.
• High Load Capacity: Boasts a 600kg (1,320lbs) Maximum Working Load (MWL) and a 1,200kg (2,650lbs) Breaking Load (BL), ensuring reliability and a strong safety margin for demanding conditions.
• Durable Construction: Built with UV-stabilized Acetal sheaves, impact and UV-resistant fiber-reinforced Nylon cheeks, and Grade 316 stainless steel components for superior corrosion resistance and extended service life.
• Smooth Operation: Self-lubricating sheave combined with polished stainless steel races guarantees efficient, low-maintenance performance.
• Flexible & Secure: The full swivel head with a slotted pin shackle allows for flexible attachment points and helps eliminate line fouling.

Applications & Pairings:

This block is perfect for mainsail sheets, halyards, vangs, and spinnaker control lines on off-the-beach catamarans, one-design classes, and sportsboats up to 8M (26'). Consider pairing with Ronstan stand-up springs or other Series 40 rigging accessories for a complete and optimized system.