Prepare your semi truck to be Ready for the Road Ahead , with the Velvac 2" Non-Locking Brass Fuel Cap that provides secure and leak-free fuel. To efficiently lock fluids in a tank, this replacement cap features a tight-fitting design that resists torque or other forces that cause similar components to loosen. Fashioned with an ergonomic body to enhance the ease of constant on / off twisting. FleetPride is your First Click in Heavy Duty .