This is the second time I've owned one of these backpacks. They're out of production, but it's a great, durable pack that fits a lot of gear. It has the theft proof zippers so nobody can unzip the pack when it's on your back.
It also has a quick access side pocket for things you need to get to quickly. It can hold a 15" laptop and my MacBook Pro fits in it nicely.
I'm downsizing my kit so I don't need a bag this large anymore.