The Topeak Fuel Tank Frame Bag 500ml Black is a handy bag that mounts to your bike's top tube. With its large capacity, this bag provides quick and easy access to energy bars, your phone, wallet, tools, or other essential items you need while cycling. Made of durable 420 denier nylon/PVC fabric, the bag features a padded main compartment for extra protection. Sturdy nylon straps securely attach the bag to your bike's top tube. The bag has a 500ml capacity and even provides access to the battery cable for charging your mobile device. Suitable for various types of cycling, including MTB, road, touring, and commuting. A mesh pocket inside the bag allows you to keep small items organized. The bag measures 17.5 x 11 x 6.35 cm and weighs 120 g. It fits top tubes with a diameter of 34-75 mm and 38-52 mm. Product specifications - Size: 17.5 x 11 x 6.35 cm - Capacity: 0.5 L - Weight: 120 g