Please Note: XS01 is a basic standalone unit; it does not support wireless interconnection, does not have Wi-Fi, and cannot be used with a base station; for interconnection, search for XS01-WR. For Wi-Fi functionality, look for XS01-WX or XS01-MR 10-Year Battery: Forget about battery changes as this alarm is equipped with a built-in lithium battery that lasts for 10 years Accurate with Fewer False Alarms: Reliably keeps you and your loved ones protected from smoke and fire; quickly detects smoke from smoldering fires thanks to advanced photoelectric sensors; low false alarm rate with air sampled 3 times every 10 seconds Fits Right In: Mini size alarm measuring just 3.1 1.9 in (78 48 mm) and with hidden mounting bracket; low-profile design makes it an unobtrusive addition to any home d?cor Fire-Retardant Construction: ABS plastic means the alarm is fire-retardant and resistant to high temperatures; ensures the alarm works even in the most dangerous of circumstances Sensitive Accurate: Built with an advanced photoelectric sensor and intelligent ST chipset, the alarm can quickly and accurately detect dangerous smoke levels from smoldering fires, and provide the earliest possible warning of fires; the dust-proof isolating plate inside the alarm ensures the detection sensitivity