This is a model of a pin-tumbler lock mechanism in the form of a small lockable box, just big enough to hold a gift card, some money, or a secret message.

Pin tumbler mechanisms are found in pretty much every lock in the world that has a straight key with one ragged edge. The version in this box is flat and made of plastic, but it shows very clearly how all such locks work: the pins, held in place with springs, block the barrel of the lock from rotating (or in this model, sliding to the left). When the key is inserted, the pins all line up exactly with the edge of the tumbler, allowing it to rotate or slide and thereby opening the lock.

The box opens easily with the supplied key, or for a challenge try to get it open using the included lock pick.

If you give this model as a gift, assembled with a card inside, you can decide whether to give the recipient the key at the same time (easy mode), just the lock pick (level 2), or neither and hide the key in some clever way that they have to figure out by following an elaborate set of clues (annoying unless they are into that sort of thing).

The kit is available pre-assembled if you just want to put a card in it and give it to that kid who is always asking how things work.

Your model will arrive attractively packaged with all the necessary parts and tools. It does not require any special model-building skills. A detailed, step-by-step assembly video is available on our instructions page.