Swann SWO-OUS1PA One Outdoor Siren (White) INTRUDER DETERRENT: An audible 104dB alarm & flashing LED light can be triggered by motion detected from sensors or cameras WEATHER RESISTANT: Weather & UV resistant ensuring durability for outdoor placement LOW BATTERY DETECTION: Via SwannOne app to indicate when the battery is low, so that you are always protected MOBILE ALERTS: Receive alerts from your Smartphone when paired with a SwannOne Smart Hub BATTERY LIFE: Uses commonly available D batteries with a typical lifespan of more than 2.5 years