Item Condition Opened box - original retail box shows some wear. In excellent condition. Opened but never been used. We have tested this for functionality. Item Location Ships from our warehouse in Las Vegas, Nevada, 89102, USA Fast FREE Shipping We handle all paid orders within 1 business day. Best Offers Accepted Offers are reviewed at the close of business each night. We accept reasonable offers for - Multiple units of the same item - Errors or condition changes within our listing - Combining shipping for 2 or more separate orders Return Policy We offer a 30 day return window from when you receive the item. Items must be in the same condition and in original packaging. Seller Warranty - We Protect Against Defects Our in-house technicians evaluate and refurbish every electronic item we list. We are proud to offer our customers a 30-day warranty against defects. Contact us directly by selecting "I have a question about using my item or I want to send the seller a message." We are eager to hear from our customers. Product Description WIRELESS INTERCONNECTED: This smoke alarm can realize the interconnection between same models. When fire detector detects smoke and the alarm sounds, other alarms connected to it will all sound. Up to 48 pcs alarms interconnect, wireless range is 328 feet SILENCE FUNCTION: If non-emergency smoke (e.g., cooking fumes) causes nuisance alerts, you can easily silence them by pressing the test/silence button of smoke alarm, false alarms can be cancelled with a single tap. Mute can last up to ten minutes HOW TO TEST: Don't test smoke detector by using burning match. Test smoke detector by pressing the test button until it beeps. The red LED of all connected devices will flash twice per second for five minutes 24 HOURS PROTECT : If you have problem in smoke alarms interconnection, please contact us. Smoke detectors should be installed in every room (except bathrooms and kitchens).