The Ortlieb Rack-Pack M is a waterproof, versatile gear/bedroll bag for travellers, cyclists and divers. The Rack-Pack M can also be used in combination with the Ortlieb Back-roller and Front-roller panniers (note! not City models). Just clip the Rack-Pack to the panniers and you've got 60-70 litres of waterproof cargo capacity! - The full-width, roll-down closure keeps water and dirt out of the bag and allows easy, fast access to your gear inside. - Heavy-duty and 100% waterproof material. - 5 YEAR WARRANTY.