first track 30 is tightly received within at least a first slot 31 and second track 32 is received tightly within at least a second slot 33 such that tracks 30 and 32 are maintained in substantially parallel relations tracks 30 and 32 are made of a hard material such as but not limited to metal which enhances the durability and performance of the tag 20 an attaching member 34 as described in greater detail hereinafter slideably rests on at least first track 30 but in a preferred embodiment rests on both first and second tracks 30 and 32 attaching member 34 has a resilient member 36 that normally maintains an opening 38 defined on said attaching member 34 in axial alignment with an aperture 40 defined on the inside of second half 24 and a hole 42 defined on the interior of first half 22 in one preferred embodiment attaching member 34 is made of spring sheet metal resilient member 36 may be a resilient lever arm 43 and in an alternate preferred embodiment as illustrated in fig7 and 9 at least one spring 44 may be substituted for the resilient lever arm 43 resilient member 36 is maintained in proximal relations to a barrier 45 such that.