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
| Brand | Groco |
| Fits | 3/4" & 1" Seacocks |
| Size | 4.29" Dia. |
| Bolt | 5/16" - 18" |