Our next rendition of the saddle bridge, the Butter Bridge, offers buttery smooth adjustment by eliminating the amsteel-on-amsteel construction that causes your prusik knots to bind after weight is applied. This was accomplished by incorporating our 100% high-tenacity polyester Vapor Line sheath into the design. As a result, the Butter Bridge is ultralight, doesn't absorb water, and is vastly more durable than alternatives. No more fraying and bridge adjustment that stays as smooth as butter even after your all-day sit.