Dimple key

A dimple key is a flat key that, instead of teeth along the edge, has small dimples milled into its faces. Each dimple has its own depth and position, and together they make up the combination that opens the cylinder.

You can recognise it because the edges are smooth and the face looks dotted with little marks. Many are reversible: they go into the lock either way up, which is handy when you are opening the door in the dark.

It is common in high security lock cylinders, because it allows many more combinations and pins in several rows. A dimple key does not on its own mean the cylinder is a good one: what counts is the whole cylinder, with its protection against bumping, picking, drilling and snapping. If you are not sure what you have, send us a photo of the cylinder and the key on WhatsApp.