The backpack you stop checking.

A packed metro, a boarding line, a crowded street. The bag is behind you, your hands are full, and the only way to keep it safe is to stay alert the whole way there.

The zippers sit under a magnetic closure that a hand behind you cannot get to — three of them on this model. When you want in, you drop one shoulder and a pulley brings the bag around to the front, without taking it off. Both of those are patented.

Built in military-grade ballistic nylon, engineered against abrasion and friction.

Ten trips in, you will have stopped noticing it — which was the whole point.