"25 Jahre Arbeit!" Small 8vo. 50 pages. Illustrated with photographs and drawings. Soft, glued covers. No signs of previous ownership. The covers are age-toned, else this intact copy remains in very good condition. The Hecker works, now known as Hecker Werke GmbH, was completely destroyed during the allied bombing campaigns of World War II. It is now one of the leading manufacturers of seals, valves and allied products that cover a wide range of applications in industry, defense, etc. A scarce item. Thanks for looking!