Abstract: A male portion (5) of an identification tag (1) has a projection or dart (6) which extends through the item to be identified. The projection is lockingly received in a corresponding passage (7) of a female member (4). One of the elements, preferably the female element, has an electronic label (8) encased therein. More specifically to be preferred embodiment, the electronic label, which is electromagnetically encodable and readable, is placed on a bottom wall (19) of a cavity (9) which is defined by peripheral side walls (11). One of the peripheral side walls and the bottom wall of the cavity define undercut or dove-tailed recesses (12). A polymer (10) is placed in the cavity in a fluid state filling the undercut recesses. The polymer is hardened, e.g. polymerized, to form a tamper proof bond with the female member.