Operating indicatorLow battery warningBattery lifeapproximately 1 yearTest buttonLoud piezo electric alarm 92dB at 3mBattery includedAvailable as a single order code YD53 or as a twin-pack order code YD54. The Micro 300 smoke and fire alarm is of compact design and is easy to install. It complies to BS5446 part one comes complete with a five year manufacturers guarantee.