Dakota Alert UTDCR-2500 Duty Cycle Universal Kit, One UT-2500 & One DCR-2500 RELIABLE & RANGE - Dakota Alert has been in business for over 25 years with a proven record of reliability and dependability for all our products. Up to a  wireless mile range. Much better range than competing products. INSTALLATION  Easy do-it-yourself installation. Mount the transmitter on a door for the magnetic contact or push button. Or connect to a N/O or N/C contact for a long range wireless transmitter. RECIEVER  Four tones to choose from; Classical, Westminster, Ding-Dong or Whistle. Volume control, also a 12 VDC output and relay output. TRANSMITTER --Runs on one CR-2 battery (included). Sends a signal up to 1/2 mile back to the receiver. Weatherproof and meant to be used outdoors. LIVE CUSTOMER SUPPORT  If you have any questions or concerns, Dakota Alert has friendly and knowledgeable staff to help.