The Sportsman fuel system uses two 15-gallon main tanks next to the inboard end of each wing, and two aux tanks just inboard of the wingtips. Dual Facet fuel pumps with 3/8" aluminum fuel tubing connects the aux tanks to the mains. The mains feed the header tanks through rubber fuel hose. In addition, a rather complicated venting system using 1/4" nylon tubing allows the tanks to breathe but not drain the fuel in most situations. We used Swageloc fittings in most connections in the wing fuel system.