The Jalan 70+15 by Berghaus is tough, versatile and big enough to travel with you around the world.  This is a no-nonsense piece of kit - robust materials, reinforced base, chunky buckles and clips - it's designed to cope with the stresses and strains of life on the road (or plane or boat).  The Jalan features Berghaus's Biofit load carrying rucsac system - very comfortable and easily adjusted for a perfect fit.  If you're about to jump on a plane just zip the harness away and the straps are safely protected from hungry carousels.  The front detaches to make a convenient 15 litre carry on board daypack (this has padded shoulder straps, a zippered front pocket with a handy clip-off keyring and a large expandable zippered main compartment).  For around town the Jalan has sturdy wheels so you can simply tow it along behind you. The Jalan has many other useful features: the 75 litre main compartment can be divided to give a seperate base compartment (handy to keep boots or dirty clothing away from your clean gear); inside the upper part of the main compartment you'll find a large zippered mesh pocket, hidden security pocket (big enough for passport and documents); side sleeve containing a useful raincover and compression straps which incorporate a handy detachable mesh bag (ideal for use as a laundry bag).  The main compartment has rugged double zippers which can be padlocked together and outside are various compression straps to keep your belongings secure.