This vintage German booklet titled "Heft 20 Flugzeug-Instrumente von Dipl.-Ing. Kurt Rehder" is a must-have for aviation enthusiasts and collectors. It provides insight into the fascinating world of aviation instruments and their history. The booklet is in good condition and contains valuable information on the subject. Whether you are an avid collector or simply interested in aviation history, this booklet is a great addition to your collection.