The ntx-r is the top-of-the-range model from the new n series and as such is compatible with the ntx receiver. It's packed full of innovative features, all designed to offer unrivalled performance. A notable feature is the battery life on all n series alarms is far better than microns of the past. The alarms also feature fox's new d-tec sensing system which elimates the need for reed switches, the first part to break if the alarm is dropped or knocked. This makes the n series super durable. Users should also expect a super crisp sound, minute volume, tone and sensitivity adjustment, multi-colour leds with fox's colour-sync system and super-reliable receiver range to name just a few of the new features. Fox micron ntx-r alarm features: Built in radio Volume control Variable tone control Intelligent sensitivity system D-tec sensing system (dtss) Led multi-colour Auto nite light 4 magnet roller wheel Sensitivity control 8 positions Drop back differentiation Power out socket Extension box socket Low level battery warning Battery 2 x aa Low battery drain Speaker type cone Set of 3 alarms and receiver (set of 4 alarms and receiver available). Factory package