This is a 1990 USAF Aircrew mask assembly quick donning MBU 12 /P oxygen mask and has a manufacture date 1990 on the side, Scott MBU 12/P mask is size Extra Long ,Date 1998, It appears to be complete with hose and intercom, the mike is in the mask, It has adjustable straps for a one size fits all. It is in very good to excellent condition and was probably used for heavy aircraft like the C-130 or KC-135 etc. ,