Bob's Plastic Throughull fitting
Requires 2 per set of hoses.
The "Bob's" style unit is a threaded unit with a large plastic nut that tightens from the inside, VS other styles that use 3 screws to attach from the outside of the boat.
This style is better as it is only drilling the one hole for the hose. However if you can not reach the inside to tighten the nut, the other style might be prefered. We have both styles here.