Flanged seacock installation is improved with the use of a backing block between the valve flange and the hull. � Each size fits multiple seacock sizes. � Press threaded inserts into the hull side of the backing block into the holes that match the seacock flange. � 1/2" thickness is rigid enough for a secure installation but flexible enough to conform to minor hull curvature. � Will not swell or absorb moisture
Will fit Groco Flanged Adapter and both Groco and Apollo Tri-Flanged Seacocks. Seacock not included.
BB-1 fits 3/4" and 1" Seacocks,
BB-2 fits 1-1/4" and 1-1/2" Seacocks,
BB-3 fits 2" and 2-1/2" Seacocks