I like this. I've used larger thru hull fittings from West Marine. I cut slits in the side of a wine bottle cork, nested the wires in the slits, stuffed the cork into the hole and gooped it with the cork keeping the goop from flowing through. For the transducer (OK Trident 13 with rear scupper mount), I drilled the hole in the sidewall of the well, reversed the thru hull mount (cause I couldn't reach inside to turn the nit), with the head inside and the threads coming out through the side wall. I then screwed the nut on with epoxy on both the head and the nut, and then cut down the threads. A little goop, and the whole thing is waterproof - no leaks.

But, I like what seem to be compression fittigs here!

Cheers.