The tags used for double tagging are known as the Primary and Secondary tags.
- The Primary Tag which may be inserted in either ear, must be made of yellow plastic and be at least 45mm in height and 55mm wide. The characters must be a minimum of 5mm high. It must bear the GB symbol of a crown, the letters UK and the unique identification number.
- The Secondary tag must be in a different ear from the primary tag. It can be made from a range of approved materials and types, including metal, button and other plastic types. It may also contain management information.
If an animal loses a tag or if it becomes illegible it must be replaced no later than 28 days after you notice the loss. Lost or illegible tags on animals born or imported after 1 January 1998 can only be replaced with a tag showing the same number, as the animal must retain its unique number for life.