Ketchum Pet License Tags (rabies tags) are produced using 0.040” plain aluminum or 0.050” coloured aluminum (blue, red, green). There are different packaging options available to you with our Pet License Tags 1. Tags strung on a wire in lots of 50 with/without attachments supplied separately. 2. Tags with either S-hooks or O-rings attached and strung on a wire in lots of 25. 3. Tags polybagged with either S-hooks or O-rings in a continuous strip.