FLANGE BOSS spreaders are mechanical, pneumatic, or hydraulic tools that safely spread flanges from 1/2" to 24" in ANSI ratings from 150 lb to 2500 lb. They are versatile for blinding, gasket jobs, and orifice plate work but must be pinned through the bolt holes for safety, especially on blind jobs. Each spreader kit includes the tool, breaker bar, socket, and storage box.