Need Antenna Recommendation For Amphibious GMRS Station

[tcp2525]

I'm looking for an antenna that is pretty much waterproof as it will be submerged at times. Possibly a Laird Phantom antenna will work? The surface area and curvature of the roof should give ample ground plane and have an optimal takeoff angle. It will need to withstand impacts from underwater obstacles. When on land, grounding shouldn't be an issue as there will be four grounding points, plus one auxiliary ground.

[Socalgmrs]

Gmrs 460mhz antennas don’t need to be grounded however most will be ground plane antennas.  And in this case no good ground plane exists. A mag mount won’t work and it’s going to be hard to get access under the roof for an nmo mount.  You’re gonna have to go with a no ground plane and an articulating lip mount.  A Rear fender might be the best spot.