Safe and Reliable These alarms are made of upgraded ABS material, fire-retardant and resistant to high temperature, durable, reliable, and with superior performance. Built to Last With 10-year sealed lithium batteries, this heat and smoke alarm kit provides 10 years of uninterrupted protection for your home, 24/7. Low Battery Warning When the battery is low, you get a full audible/visual warning telling you when to replace the device. 85 dB Volume A loud sound of over 85 dB will be emitted throughout the home when triggered. Everyone will immediately hear the alarm, even in deep sleep.