This is an example of the U.S. Navy, Gentex MBU-23/P oxygen mask. It is designed for use in tactical aircraft for both pressure breathing and non-pressure breathing applications. This particular mask has a field modification of a digital desert camouflage cover.

This oxygen mask was worn by the donor Capt. Matthew Dwyer. He was the first 1st Lieutenant selected by the Marine Corps to fly the MV-22 out of Marine Squadron VT-2 in Milton, Florida. He then received V-22 flight training in VMMT-204 in August 2006 and was assigned to VMM-162, the second operational V-22 squadron. He was then assigned as the Aviation Life Support Systems officer and deployed to Al Asad Air base in Iraq March-October 2008. He had the privilege of flying Barack Obama, then the Democratic presidential candidate, from Ar Ramadi, Iraq to Amman, Jordan, a flight only capable in a V-22 aircraft. Following his deployment and flying numerous combat missions in the Middle East, he was then deployed with VMM-162 (reinforced) as part of the 24th Marine Expeditionary Unit in 2010 to Haiti for humanitarian assistance and disaster relief after the earthquake.