The skull itself is based on the Axis Scientific 3-piece skull, a life sized skull model cast from a natural specimen. Uniquely, the Axis line of skulls does not have much visible external hardware The removable calvarium is held in place securely with a pair of magnets and series of small pegs, allowing for a largely uninterrupted study of the skull. The mandible is held in place with high quality springs that allow natural movements of the jaw. The bony structures of the skull are identifiable with the use of the included colorful key card. Each bone and bony pair is painted a unique bright color for quick identification using the card. Bones that exist as pairs (ex. Parietal bones) are identified as a single color, making it even easier to locate both on the fly. All bones of the facial and cranial structure are identified with this model, with the exception of the auditory ossicles. For those interested in the structure and features of the ear, check out the Axis Scientific Oversized 3-Part Human Ear, a tremendous model of the structures of the human ear, including auditory ossicles. Axis Scientific offers the best combination of price and detail in the industry, plus expert customer support to help you now and through the life of your Axis product. Contact our support team with questions, or help finding the perfect model for you. Made by Axis Scientific and backed by a 3 year warranty. Measures 8x7x5 inches. Weighs 2 lb.