Groco Backing Blocks

• Each size fits multiple seacock sizes.
• Press threaded brass inserts into the hull side of the
backing block into the holes that match the seacock
flange.
• Rigid 1/2” thickness provides secure installation but
is flexible enough to conform to minor hull curvature.
• Will not swell or absorb moisture.
• Made from an environmentally friendly PVC foam
specially formulated for marine applications.