When you're going to the toilet in a club or bar, you probably don't pay much attention to the hook on the back of the door.
But police have in the recent past issued warnings about dodgy coat hooks installed to spy on punters.
If you see one, you should leave immediately and report it to the police.
The hooks are freely available to buy online for as little as £12 on auction sites.
They look like regular coat hooks, but contain a hidden spy camera.
Police in the US warned that the hooks were being installed inside public toilets used by women.
The cameras film in full colour HD.
So next time you're out - remember to check the back of the toilet door.