Barton Marine Size 4 58mm Plain-Bearing Upright Block

The Barton Marine Size 4 58mm Plain-Bearing Upright Block is built for sail-control systems that need a strong, compact change of line direction. Barton Marine's plain-bearing block construction uses molded sheaves and corrosion-resistant internal hardware to keep the line running smoothly under load. Through-bolted and riveted construction adds security at the side plates, while the specified swivel, becket, upright, or stand-up configuration suits the intended rigging layout. The block is sized for cruising and racing applications where dependable load handling matters more than unnecessary complexity.

They are of a rugged construction featuring high-grade molded side plates that are through-bolted and riveted for added strength and security. All load-bearing components and interior frame are from marine grade 316 stainless steel and both plain and ball-bearing sheaves are available. This sleek and versatile range is engineered for use on larger cruising and racing yachts and is compatible with Barton Marine's ball-bearing mainsheet traveler system. The 54mm sheave Size 4 range is of rugged construction, featuring high-grade molded side plates that are through-bolted and riveted for added strength and security. All load-carrying components and interior frame are from marine grade 316 stainless steel and both plain and ball bearing sheaves are available. This sleek and versatile range is engineered for use on larger cruising and racing yachts and is compatible with Barton Marine's ball bearing mainsheet traveller system.

• Built for repeated line-direction changes under sailing loads
• Corrosion-resistant construction suits exposed deck service
• Compact hardware helps keep rigging systems organized
• Designed to maintain a fair line lead through the sheave

For the Size 4 58mm Plain-Bearing Upright Block, match the block to the rope diameter and safe working load specified for the model, and keep the lead aligned with the sheave to avoid unnecessary side load. Swivel, becket, upright, and stand-up versions each solve a different rigging problem, so the attachment style should be chosen around the intended purchase or turning point. For more blocks and line-control components, browse more Sailing Hardware.