The Mag-Tank™ takes a new twist on top tube bags. Instead of a zippered opening, access to the bag is by a smartly contoured top flap held in place by a magnetic buckle with mechanical engagement (the magnet aids in closure, while the load is placed on a connection). Unlike a conventional magnetic closure, the Mag-Tank will not unintentionally open when you end up in the trees with your bike upside down. You can easily open the bag one-handed by pulling outward on the cord loop and you have access to the whole top of the bag. To close, just flick the flap down and the buckle self-engages! Compared to Revelate's standard Gas Tank, the Mag-Tank is just a hair smaller to prevent leg movement from hitting the edge of the flap opening.

Note: While the cover to this bag is designed to shed rain and spray, due to the large panel opening it is not a sealed bag or waterproof bag. Additionally, while the closure is secure there is the possibility that small or loose objects can come out of the bag from rough trails or lying the bike on its side. They recommend small items like loose keys and gummy bears are put in a ziplock.