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The parachutist's beacon and parachute were similar to the ones seen in the supply drop.
The parachutist was wearing a pressure-demand oxygen mask, as opposed to a continuous-flow mask. Continuous-flow masks (such as of the kind released in airliners during emergencies) are typically used in unpressurized aircraft that fly between 12000 and 25000 feet, and do not make an airtight seal around the mouth. Pressure-demand oxygen masks like the one worn by the parachutist make an airtight seal and allow for flight at altitudes up to 50000 feet (if the aircraft is pressurized and the composition and pressure of the oxygen can be controlled). Flight above 50000 feet typically requires an astronaut-like pressurized suit. While some helicopters have flown to 40000 feet for the sake of claiming records, few helicopters can fly higher than 20000 feet, and most operate at 10000 feet or below (and thus are not pressurized).

A little Lostpedia info about the parachutist!!