The twentyfourseven plus 25 daysack from berghaus is a lightweight practical and versatile rucksack that is ideal for walking rambling cycling commuting and everyday use the raised vented foam panels on the flow back system coupled with the padded adjustable straps offer improved breathability and comfort for you while you are wearing your twentyfourseven pack and the height adjustable chest strap can be used when you need to distribute some of the weight of you pack making this a great versatil