Made from 5051 aircraft aluminum alloy, Speedmaster™ aluminum fuel cells offer superior strength in a lightweight package. The cells have foam in the base to prevent fuel aeration, and have TIG-welded seams. Other features include a flush mount, aircraft-style cap and -10 AN pickup, vent, and return line fittings. Plus, all our models include a 0-90 ohm GM sending unit. Not to be used with methanol.