The Volume Reducer is a clear plastic bag with zip closure, used to compress the contents of your bag or rucksack and leave you with more packing space making it a very useful item when you\\\'re planning a trip. Instructions Place items in bag, close zip ensuring a good seal. Roll bag up slowly from zip end to squeeze air out. Flatten bag, turn over and repeat to completely compress. Always roll bag on soft surface for maximum life and do not put sharp objects in it