Original issue, US Army Technical Manual, 169 pages plus 6 fold out pages of block diagrams, size is 8 1/4" x 10 3/4", stapled, three hole punched, dated 24 November 1970.  This not a commercial copy or print but an original issue government print issued in 1970.  This publication is titled - TM 11-5840-281-12, Operator and Organizational Maintenance for Radar Set AN/TPN-18.  Publication is designed to provide information and instructions for the operation and  repair and maintenance requirements and procedures for this radar set. Very well illustrated using photographs and line drawings.