Abstract: An anti-removal monitoring device which may be strapped to a person's appendage or to a piece of equipment. Once activated, the device transmits a signature encoded RF signal distinguishable from others to be monitored by a receiving station. If either the person or the device moves or is removed to a range out of signal reception, or if tampered with as by cutting the strap, such alteration of the normal signal is detected at the receiving station. The device comprises, in one embodiment, a transmitter housing for electrical connection to a base in a manner sealing the connection against the elements, and with a biased piston movably mounted within the base for operative connection with both ends of the strap and for activation of the transmitter only upon completed securement of the strap ends about the appendage or equipment and into the base.