Abstract: A pulse oximeter is provided comprising a housing that includes three-dimensional surface elements on upper and lower sections of the housing that are configured to resemble an animal or an object. The pulse oximeter is configured to receive a finger or an ear of a user to measure pulse and oxygen saturation of the user, and the three-dimensional surface elements of the upper housing and lower housing are collectively configured to resemble a mouth and a face of the animal or object for receiving the finger or ear of the user into the pulse oximeter. The housing can be permanently attached to the pulse oximeter or removable from the pulse oximeter so as to be replaceable with an alternate housing having different three-dimensional surface elements resembling a different animal or object.