FireHawk 10 Year Battery Heat Alarm | 1787-22 Advanced Thermistor Detection Auto Switch Mounting Plate Alarm Silence Button Silence Low Battery Warning Interlinkable Version LED Indicator Test Button FireHawk 10 Year Battery Heat Alarm | 1787-22 Features Advanced Thermistor Detection - controlled by bespoke software. Auto Switch Mounting Plate - Power automatically switched on when the alarm is attached to its mounting plate and off when removed. Alarm Silence Button - Ideal in non-emergency situations (nuisance alarms) Silence Low Battery Warning - For up to 10 hours. Maintains continuous protection during sleeping hours Interlinkable Version – FHH10W available for interlinking to smoke alarms Test Button - Extra large Test Button for ease of use LED Indicator - Red led flashes once a minute to indicate power and constantly flashes to indicates alarm condition Sealed in 10 year Lithium battery power supply