Abstract: An underwater breathing apparatus is provided for delivering air to a diver submerged to a depth between one and 12 feet. A pump delivers air at low pressure via an expandable air hose to a regulator worn by the diver. The air hose provides a reservoir of air for the supply the diver. Upon inhalation by the diver, the air pressure within the diver's lungs is reduced, thereby causing a tilt valve located within the regulator opens to allow air from the air hose to be supplied to the diver until the air pressure within the diver's lungs is equal to the air pressure generated by the pump in the air hose, which in turn causes the tilt valve to close. An exhalation one-way valve is also provided in the regulator to allow the diver to exhale without forcing the exhaled air back into the air hose.

Abstract: A removable wheel guard for an in-line type skate. The guard includes an elongated channel to receive the wheels with an upwardly curved forward portion to inwardly receive the front wheel. An adjustable bridle is coupled to the base of the channel for the purpose of firmly attaching the guard to the rear of the skate.

Abstract: A portable hyperbaric chamber is provided that allows a person to perform endurance exercise at barometric pressures of from 0 to 10 lbs./square inch greater than ambient. The chamber is portable, semi-spherical and inexpensively constructed of an essentially air-impermeable, flexible material. This invention is a closed circuit rebreather using an oxygen supply and carbon dioxide removal means to provide an extended period of breathing without the need for attention to maintaining a fresh air supply. This system is designed for ease of use, low cost, and light weight. It utilizes reusable parts and a limited use pressure chamber and breathing bladder. This system features a lightweight pressure holding closure system which does not rely on expensive zippers and is stored in the pump unit which pressurizes it.