This model is a Tell Your Dog I Said Who's A Good Boy hanging charm / keychain!
This charm is 13cm wide, 3.3cm tall and is 6mm thick.
Charms are designed with a 'channel' to allow for a 2.4mm (or smaller) ball chain to be looped through. Ball chain is available very cheap online in a variety of colours - we suggest cutting the ball chain to a length of 25cm.