What's the Smallest Tilt sensor (or garage door sensor)

As the title says. Wanting to add to a live trap for an indicator. Someone else did this with a door sensor, but this way looks easier.

Someone posted one once that looked about the size of a quarter.

Edit - really need Z-wave (distance, other Z-wave close, etc.)

Check out the nyce ones from Lowe’s

http://nycesensors.com/products/ncz3014/

Right size - forgot to add I really need Zwave.