Barton Marine Size 7 Single Plain Bearing Stand-Up Blocks. This range of high-load cruiser bocks is of rugged construction featuring high-quality injection molded side plates with all load-carrying components from 316-grade stainless steel. Side plates are through-bolted and riveted for added strength and security. Specifications for Barton Marine Size 7 Single Plain Bearing Stand-Up Block: Manufacturer: Barton Marine Color: Black Package Contents: Barton Marine Size 7 Single Plain Bearing Stand-Up Block Barton Marine N07170: Size 7 Single Plain Bearing Stand-Up Blocks