The bite bar is the bar on the left that is “L” shaped. It swings and can be raised and lowered (to a point). But it’s about exactly the correct height when the bottom is flush with the base. The curved bars are the eye bars and they have little divots that fit into the bottom of the orbit. They too are exactly the correct height to have the animals’ head in a good, stereotaxic position. The eye bars are on a little slider that you slide along the base so they reach the eyes and they are exactly the correct width for an adult (female) ferret. They can also rotate since the eyes are slightly sideways on the head.
Kopf Instruments Ferret/Mink stereotaxic adapter and ear bars [link]
Infrared warming: It is possible to use the Kent Scientific far-infrared warming system with ferrets. However, the rat temperature probe is too short to be used with adult ferrets. Kent Scientific will make a custom temperature probe for you ($158). The right length is 3.5 inches (8.9cm). The far-infrared warming system provides superior temperature regulation and also greatly reduces the likelihood of skin burns (VH Lab).