A heavy duty and extra large high quality slide rule made most of wood and metal and comes in the original military color wooden carry box. There is also an original canvas bag inside with drawing tools. All items are original German Army (Bundewehr) Equipment until replaced by digital equipment in the 1970’s. this instrument is called a “Streckenzugtafel” and has the number Aristo 1780, it is also signed Dennert & Pape / Aristo – Werke on the outside would box along with the German Army registration number 6675-12-127-2366. Made for the making artillery calculations in the field. It is complete, working and in great condition. It measures about 40 x 40 com or 16 x 16 inches in the box. Check the attached video on how to work your vintage man tool : slide rule operation instructions!