Barton Marine Size 7 Single Plain Bearing Stand-Up Block

The Barton Marine Size 7 Single Plain Bearing Stand-Up Block is a precision-engineered rigging component designed for serious cruising sailors and offshore boaters who demand reliability under the most demanding conditions. This single block serves as the workhorse in mainsheet systems, topping lifts, and other high-load applications where smooth operation and durability are non-negotiable. Built by Barton Marine, a respected UK manufacturer with decades of marine engineering expertise, this block is engineered for vessels ranging from 30-foot coastal cruisers to larger offshore passage-makers.

The heart of this block's performance lies in its plain bearing construction, featuring a precision-molded acetal sheave that runs on a large-diameter brass bearing—a combination that ensures free-running operation even under extreme loads. Unlike roller bearings that can jam with salt or debris, the plain bearing design is inherently self-cleaning and requires minimal maintenance in saltwater environments. The stand-up configuration keeps the block vertical, preventing line slip and providing efficient load transfer, while the rugged, compact footprint (4 × 2 × 8 inches, weighing just 1 pound) makes it easy to integrate into existing rigging systems without adding unnecessary weight aloft.

This Size 7 block is ideal for boaters upgrading aging hardware or outfitting new vessels with systems that will survive years of offshore use without failure. Whether you're wrestling with a mainsail in heavy air, managing topping lift loads on a boom, or running any mid-range running backstay system, this block's high-load capacity and forgiving design make it the choice of experienced cruisers. Installation is straightforward on any standard deck or spar attachment point, and its proven Barton Marine pedigree means you're investing in equipment that will outlast the boat.