The easiest way to identify the model of alarm on a keychain is to use specialized Internet sites that host photos of the key chains from the most common signaling systems.
For example, on the website on the page contains a selection of photos trinkets, the number of which is constantly updated. If your key FOB will fully comply with one of the photos, then you have successfully identified.
The website different from the previous ones in that page you'll be able to set search parameters you are interested in keychain, sort available information according to the following criteria: the number of buttons and the display or LEDs.
If you have no Internet connection at hand, carefully inspect a car alarm: it is the manufacturer and model may be listed somewhere on the case of fine print or in inconspicuous place.
If the case is a keychain will not contain any information, pay attention to its design features, because some manufacturers endow keychains unique design, unique to this brand. For example, key chains alarm Pharaon have a surface similar to marble, remote controls Mongoose engraved image of a silhouette running mongoose, keychains Sirio Tank are similar to tank the tower and Cobra keychains remind the bulging hood of this snake.