A set of CAD drawings to illustrate a method of creating electrical thru-hulls for a submersible using Stainless-Steel pipe fittings.   A one-inch coupling or nipple is welded to the sub hull.   A two-inch to one-inch reducing coupling (or bell coupling) is filled with epoxy.   The reduction in size restricts the epoxy from creeping or extruding due to outside water pressure. These drawings show a coupling welded into the hull, however a nipple could be used instead.   The drawings also show common wire for the electrical connection, but threaded rod is better.