The original alarm horn on my truck failed after about five years. After verifying that the horn was bad, plain as day I was still able to read the make and model stamped on the back.

This revision sounded a bit different (higher pitched), and also featured an optional reduced volume arm/disarm tone (Soft Chirp). This option allows the alarm to sound at full volume, but not draw so much attention when locking/unlocking doors. This option is easily defeated by simply cutting a wire loop if not desired.

My only complaint is that my old alarm horn seemed to be a bit louder. Aside from that, this was the exact model of my old one and retains full functionality.