This is a vintage Systron Donner Instruments catalog from 1974. It features a wide range of products, including manuals and books for test equipment. The catalog is in good condition and provides a unique glimpse into the world of 1970s technology. The brand is well-known and respected in the industry, making this catalog a valuable addition to any collection. Whether you are a collector, historian, or simply interested in vintage technology, this catalog is a must-have.