Tunnisteen käsittävä hylsy

A paper roll core, which includes a tag and wherein the tag is a tag which is radio-readable and includes a flexible element. The core has its end face provided with a recess with a bottom and a wall, in which the tag is fitted in an at least partially coiled configuration. For example, the tag can be glued in the recess. Alternatively or additionally, the tag can be retained substantially stationary by a springback force evolved as a result of coiling the flexible element, bracing the flexible element against a wall and/or a bottom included in the recess.