Abstract: A tag for use with an electronic monitoring system for monitoring an object, which includes a housing enclosing electronic circuitry which includes a transmitter for transmitting a signal to a location remote from the tag, two straps connected to the housing and including an open electrical circuit, and a mechanism for mechanically and electrically connecting and locking the housing to a limb of the user which includes a base member and a cover member which, when forced together with the ends of the two straps between them, bring about an irreversible mechanical locking and simultaneously close the circuit running through the straps, preferably in a circuitous manner. In another embodiment, a secondary transmitter located in one of the straps transmits to a receiver located in the housing. Analysis of the received signals provides an indication of the proximity of the secondary transmitter to the object being monitored.