The First Alert 1039802 Ionized Smoke Alarm utilizes ionization smoke-sensing technology paired with an advanced smoke-gathering design to effectively detect smoke from flaming fires. It emits a loud 85-decibel alarm to ensure you can hear it clearly during emergencies. This smoke detector is equipped with a user-friendly single test/silence button, making operation straightforward. Additionally, it features a side-load battery compartment with a theft-prevention lock and tamper-resistant battery operation for enhanced security and reliability. Protect your home with confidence, purchase this dependable smoke alarm today!