Mag TankDescription The Mag Tank takes a new twist on top tube bike bags by doing away with a zipper! The Mag Tank features a smartly contoured top flap secured by a magnetic buckle with mechanical engagement, ensuring no accidental openings, even when your bike is upside down. With one handed operation, simply pull the cord loop outward for full top access; closing is a breeze with a simple flick of the flap. The Mag Tank excels at fast on the go access to