The Smartwares SC50-6 is a compact alarm system for small spaces such as an apartment, shed, or a garden house. The starter kit consists of a base station, 2 motion detectors, 2 magnetic contacts, and 2 remote controls with a range of up to 25 meters. The entire set is battery powered. An LED light located on the base station indicates whether the batteries need to be replaced, so remember to keep an eye on the light.
You can use the adhesive strips to position the sensors wherever you want in the space in question. The sensors communicate wirelessly, so there's no problem involving cables. When the system detects something, it'll set of an alarm with a 100-decibel audio signal. That's more than loud enough to scare off any intruder.