Cheap Roxy The Good Life 41L Wheeled backpack 

The Roxy Good Life is one of the most versatile pieces of luggage in their entire range. You can wear it like a backpack or deploy the hidden telescopic handle and tow it on its smooth running wheeles. According to Roxy the Good Life can be used as 'hand luggage' which meens its small enough to be stowed in the overhead lockers on a plane. You get 41 litres capacity with a front zip pocket an ID holder and an external magazine sleeve.