Supervised wireless door alarm helps stop unauthorized exits and entries of fire/emergency doors. When activated, the STI-6400WIR4 emits an ear piercing alarm for 30 seconds, three minutes or continuously and sends a radio signal, alerting it has been triggered, to included 4-Channel Receiver (range up to 1000’ line of sight). Volume choices include 95 or 105 decibels. The alarm can serve as an inexpensive workplace alarming device and helps stop theft as well. Standalone unit also available.
More Info: http://www.sti-usa.com/cd18