1. Frequency: 433.9MHz 2.Coverage: 200M 3. Vibrate/ Beep/ Sounds 4. It can work with 16 pcs pagers SU-166 Specifications:1. Frequency: 433.9MHz2.Coverage: 200M3. Power: DC 7.5V-4A4. It can work with 16 pcs pagers SU-1665. Alert: Vibrate, Flash, Beep6. Very competitive price7. One year Warranty Wireless Pager- Transmitter SU-160