This is essentially a small diving bell that fits over the user's head and allows him to descend to moderate depths. It does not protect the user from pressure, but could be easily modified to do so. It should be noted that I am not responsible for any injuries sustained while using this device; If, however, you take the proper precautions, the possibility of this is small, even in the event of a pressure failure. This helmet can be made from simple, inexpensive materials. It can be operated by two people, and with some design modifications, could be made self - contained. I have made sustained dives of over two minutes without a problem, at depths of approximately ten feet.