Original issue, US Army Technical Manual, 29 pages, size is 4" x 5 3/4", stapled, dated 10 February 1975.  This is not a commercial copy or print but an original issue government print issued in 1975 and republished in 1982.  This publication is titled - TM 3-6665-303-10, Operator's Manual for Calculator Set, Radiac and Nuclear Yield: ABC-M28A1.  Manual is designed to provide complete information and instructions for the use and operation of the M28A1.  Well illustrated using photographs and line drawings.