This is a rare Vietnam War vintage 1968 USN & USMC pilot and crew oxygen mask Type MS22001 with microphone and the rare butterfly clips. It has a date of 1968 on the mask. It is a size medium. The mask is made by Sierra. The rubber is in excellent condition. It is a complete mask with the proper connectors, valves and microphone. This mask would have been used with the APH-6 flight helmet. The item “Rare! 1968 USN USMC Pilot’s MS22001 Oxygen Mask With Mike & Butteryfly Clips” is in sale since Thursday, November 09, 2017. This item is in the category “Collectibles\Militaria\Vietnam (1961-75)\Original Period Items\Personal, Field Gear”. The seller is “dauntlessaviation” and is located in Apache Junction, Arizona. This item can be shipped worldwide.