Groco Seacock Backing Block 3 -4" Seacocks GRO BB4

Groco Seacock Backing Block 3 -4" Seacocks GRO BB4

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.

Size: 9.5" Dia.
Fits: 3" & 4" Seacocks
Bolt: 1/2" - 13"

SKU: GRO BB4
Manufacturer: Groco
Category: Plumbing/Seacocks/