Specification：
| Model NO | SR-818 |
| Input voltage | DC3V battery |
| Standby Current | <5μA |
| Alarm Status | <30mA |
| Alarm Sound | >85dB/3M |
| Wireless interconnection frequency | 433MHz |
| Zigbee Wireless signal | 433.92M GFSK |
| Wireless transmitting distance | 200m (open area) |
| Battery life | 5-8 years |
| Alarm concentration | 13% |
| Temperature range | -10ºC~+50ºC |
| Humidity | 0%~95%RH(No condensation) |
| Sensitivity | 0.5dB/m (±0.1dB/m) |
| Standard | CE |
| Auto reset | Yes |
| size | 10*10*4.5cm |
more detail:https://www.firealarmfactory.com/interlinked-smoke-alarms.html
