Hispec RFSMOKE9V Radio Frequency Smoke detector Battery Operated Wireless Alarms-Lithium\r\n- Designed to offer the fastest and most efficient wireless circuit around the home.- Powered by a 3v 10 year sealed lithium battery.- Connect up to 20 smoke & heat alarms.- Transmitting & receiving distance 50 m.- Test function/hush feature.\r\nThe HiSpec RF10-PRO range of safety alarms offers an easy way to upgrade your home smoke alarm system to comply with new regulations. Each alarm is completely wireless powered off a sealed 10-year life battery and connected via radio frequency to all other alarms in the house. No electrician is required, these alarms are a much faster and cheaper alternative to having the alarms hard-wired.\r\nFeatures:\r\n- Brand: Hispec.- Battery only with integrated RF technology.- Activated by twist and click mounting bracket.- Loud 85dB alarm.- Mounting plate included.- Insect proof.- Easy installation.- Compatible with Hispec control unit.