Original laboratory trade vintage catalog for SIMPLEX VALVE & METER COMPANY, main office was located at 2019 South 68th Street, Philadelphia, PA. Manufacturers of Simplex Meter Registers, Simplex Hot and Cold Meters, Venturi Tubes, Pitot Tubes and Manometers. Rate of flow controllers, loss of heat, water level gauges and altitude valves. Unbound from a large 1931 engineering catalog, this unique old one page technical specifications brochure would exhibit beautifully matted and framed. A fantastic addition to your retro industrial instrument collection. Slight damp stain on outer edge.