The Expedition System is built around a simple idea: three sizes, one system. Each dry bag is engineered to work independently, but they are at their best when you carry them together — layered, organised and ready for whatever the day brings.
The 2L is for the essentials you reach for often. Phone, wallet, keys, headtorch, a spare pair of socks. It slips inside a jacket or the top of a pack, and keeps small items dry through river crossings, sea spray and unexpected downpours.
The 5L is the everyday workhorse. Camera body, extra layer, first-aid kit, a day's worth of food. It is the piece most people underestimate and end up using the most.
The 10L carries the bulk — sleeping layers, cooking gear, dry clothes for camp. It anchors the system and, on shorter trips, can carry almost everything you need on its own.
If you are unsure, start with the 5L. If you already know the trip, choose the sizes that match the pieces you rely on. The system rewards planning, but forgives improvisation.