Elastic fitting waterproof and lightweight cover in day glo yellow this single layer cover gives extra protection from rain dust or snow and is ideal for boat trips to protect against spray the day glo yellow also can be used if the visibility drops enabling you to be seen by others or in an emergency when signalling for helpcan also be used to protect the straps and back panel of your rucksack if being used in a hide or on muddy ground designed to fit rucksacks up to 40l