Pre-vent #1 Fill Cap Fuel Tank Cap

Designed for use on small above-ground farm and commercial gasoline and distillate storage tanks. May be used for fuel transfer tanks and small oil storage tanks. Pressurizes tank to reduce evaporation loss. Cap valve opens at 2-1/2 lbs. to reduce pressure. Lockable. Fits 2" NPT tank openings. Desc.: Pre-Vent I fill cap