However, pumps with capacities of less than 1,000 gph are commonly molded with a plastic, threaded through-hull fitting and are sealed to the hull with a nut, gaskets and sealant on the outboard side. This practice is common in top-shelf bass and bay boats for a couple of reasons. First, it’s not always easy to mount the pump, as required, below the static water line when stacked on a through-hull fitting. Second, in boats where these small-capacity pumps are used, they are mounted in tiny compartments where a through-hull’s greatest enemy — an errantly placed foot or elbow — is prohibited anyway. So, we’ll nod at the practice in those circumstances.