Tank Penetration Fittings are the "Sensors" of the Tank Tender System. As part of a simple pneumatic/mechanical system, Tank Penetration Fittings are simply a threaded fitting with a 30" long, thin, stiff tube attached. The fitting is installed in the top* of the tank over the deepest spot. The stiff air tube is cut to length so it terminates just above the bottom of the tank. The TPF comes standard with tubing long enough for a 30" deep tank, but an Extender Tube can be added to reach a maximum tank depth of 60".

After installation, the top fitting is connected to the Tank Tender panel via a length of 1/8" flexible nylon tubing, which is sold separately. See Related Products, below.
All connections are simple, easy "push-in" connections.

Each tank requires its own Tank Penetration Fitting (TPF)
Tanks from 30" to 60" deep will also require an Extender Tube (EXT)
Tank Penetration Fitting installation requires drilling and tapping a 5/32" hole in the top of the tank using a #21 drill bit and a 10-32 thread tap. Recommended minimum tank top thickness is 1/16" steel or 1/8" fiberglass

* If necessary, Tank Penetration Fittings can be installed in the side of a tank near the bottom, but this is not recommended.