A U.S. Department of Defense, Bureau of Ordnance Publication Issued Tech Manual Titled "Optical Equipment: Rangefinder Mark 53 Mod 0 and 1" in good condition overall. This manual is post-WWII dated May 1946. It includes several pictures, figures and pertinent specifications to the above listed equipment. Once classified "Restricted" it has been declassified and is available to the public. About the Mark 53: A mechanical coincidence-style optical rangefinder. Used primarily during World War II and the Cold War. It was famously mounted in the forward-most gun turret (Turret I) of the Iowa-class battleships. Used to calculate the precise distance of naval targets for the ship's massive 16-inch guns. Unlike the stereoscopic rangefinders (Mark 52) used in the other turrets, the Mark 53 utilized a special astigmatic lens that allowed operators to focus clearly on a single-point light source, such as an enemy searchlight. Bidders are welcome to preview items in person during our normal operating hours Tuesday through Saturday 11am-6pm. Estimated shipping parcel size (LxWxH) 14 inches x 12 inches x 4 inches. Please note, shipping estimates are provided for LiveShipping calculations only and may vary based on weight and location. The auction house will combine multiple lots to reduce shipping cost. Please inform the auction house prior to paying your invoice for special shipping requests. Our primary method of shipping is via UPS Ground.