Groco Flush Mount Bronze Thru-Hull Fittings are threaded with NPS (straight) male pipe threads and are designed for use with Groco Seacocks or any similar product with NPS female threads.

These thru-hull fittings can also be used with NPT (tapered) threads in low pressure installations only. When connecting to tapered threads, a generous amount of pipe sealant or PTFE thread tape is absolutely required.

Groco thru-hulls are the best choice for below the waterline installations. Available with or without the bronze locknut with a bonding screw, or may be threaded directly into a compatible seacock.