This solid state pump measures only 3″ in all directions, and weighs only 18 oz. All steel metal case that mounts with two bolts. All models feature: no internal check valves-free flowing-may be mounted inline w/mechanical pump to use as standby or booster pump. (Fuel will seep back thru when engine is shut off). Not to be used with fuel injections. Self priming, may be used with all fuels.