Product feature:

1.Photoelectric sensing technology;
2.Test button-to verify unit's electronic circuitry, horn and battery;
3.Audible and visible alarm-Loud 85dB(3m) with Red LED flashing;
4.Low battery warning-Smoke detector will chirp when the battery is low;
5.Tamper resist-Helps deter alarm tampering or theft;

Technical data:

Photoelectric Smoke Detector

1) Material: ABS plastic
2) Assembly no wiring, size: Dia.102xH35mm
3) Power supply:9V carbon zinc battery/PP3(battery included)
4) Standby current: 8μA, Alarm current: 16mA
5) Environment temperature: -10°C ~ +50°C
6) Environment humidity: 10% to 95%(40±2°C) 
7) Alarm decibel: louder than 85dB at 10feet(3 meters)
8) Tamper Resist locking pin
9) Test button:To verify the proper functioning of the detector
10) Low voltage warning: Unit beeps every 40 seconds for 30 days (minimum) to indicate a need of battery replacement 
11) Smoke sensitivity:0.086 dB/m to 0.140 dB/m
12) CE, ROHS, EN 14604
13) 5 years quality guarantee         

Installation reference:

• 
  Smoke Detector with Hush PW-509SQ
• 
  Combined smoke and heat detector PW-560SH
• 
  Smoke Detector PW-521
• 
  Smoke Detector PW-518B1
• 
  WIFI Smoke Detector PW-518B2W
• 
  Smoke Detector PW-518B3