The Barton Size 3 45mm Plain Bearing Pulley Block Double Upright Block (N03250) is a compact double-sheave sailing block that delivers a strong lightweight purchase for mainsheets vangs and lead blocks on dinghies dayboats and lightweight cruisers.

Sailors often need reliable low-weight blocks that resist corrosion and wear. This block solves that by combining engineered materials and a simple plain bearing design for predictable performance with minimal maintenance so you can focus on sail trim not hardware service.

• 45mm (Size 3) Acetal sheaves for low friction and consistent rope run
• 30% glass-filled nylon body for increased stiffness and strength compared to unfilled nylon
• Stainless steel frame for corrosion resistance in marine environments
• Plain bearing construction for simplicity and low upkeep
• Rated for use with up to 10mm (3/8 in) rope for common dinghy and dayboat lines

Compared to heavier all-metal blocks this upright double block reduces weight without sacrificing load capability making it suitable where compact powerful purchase systems are required. Use it as a mainsheet block vang lead block or wherever a paired sheave setup improves mechanical advantage in your rig.

Manufactured by Barton Marine part number N03250 this block uses identifiable materials and construction you can cite: Acetal sheaves 30% glass-filled nylon body and stainless steel frame. Fit it to your existing padeyes or shackles and pair with compatible 10mm rope for reliable service. Discover more details or order replacement blocks to match your boat's setup.