Original issue, US Army Technical Manual, 235 pages, size is 5 3/4" x 4", stapled, dated 23 October 1985.  This is not a commercial copy or print but an original manual published in 1985.  Title of publication is -  TM 9-1015-200-10, Operator Manual for Mortar, 81 MM, M29A1.  Publication is designed to provide information and instructions for the use and operation of the 81 MM mortar in all conditions.  Very well illustrated using extremely clear and detailed line drawings.