A tag for identifying an item to which it is attached includes an inductance connected in parallel with a capacitance. The capacitance includes a plurality of individual capacitors, each of a predetermined different capacitance. The individual capacitors are connected to the inductance to establish a resonant circuit having a predetermined resonant frequency. At least one of the capacitors includes a dimple for shorting the capacitor when the tag is exposed to electromagnetic energy at the predetermined resonant frequency. The shorted capacitor establishes a second resonant frequency which may be used to identify which capacitor has become shorted. A binary "1" is assigned to either the shorted capacitor or the non shorted capacitor and a binary "0" is assigned to the capacitors which are not assigned a binary "1", the binary "1"s and "0"s combining to establish a numeric code uniquely associated with the tag.