The SGM-4 Head Holder is designed for fixing the head simply, for non-stereotaxic fixation. Since the compact design allows itself a low gravity fixation, it can be set under the microscope stage. The clamping method is based on 3 point fixation (mouth, nose and ear) that makes the stable fixation. The nosepiece can be detachable and changeable by using the dedicated anesthetic mask, and it will be easily moved onto the experiment with use of anesthesia. By attaching the holding instrument to a single bar, it is enable to fix the head stably and allows the head angle to be freely adjusted through 360°. The shape and functions are simple, yet this holder can be used for many different purposes. The SGM-3 is for rats. The SGM-4 Head Holder is for mice. The SG-3N (for rats) and SG-4N (for mice) without the accessories of anesthetic mask and tilt adjustment mechanism are also available.