When heading our for a weekend or longer trek, you'l need to take more kit for sleeping, shelter, cooking etc so a larger pack is required. Larger rucksacks are generally packs over around 40 litres which are designed to carry all of your gear when camping or backpacking, often over long distances or for extended periods of time. To make the expericnce as enjoyable as possible, it’s vital that the rucksack is a good fit and is comfortable to carry.