The bunny ears are filled with crinkling paper.

Small: body diameter 3.125" or 8cm, perfect for XS-M pets
Medium: body diameter 5" or 13cm, perfect for M pets

Each pup plays differently and we recommend you to keep a close watch particularly during the first time a new play object is introduced. No toy is completely indestructible, so please supervise the play to ensure safety if you know your pup is not gentle with toys.