Original oil and gas trade magazine vintage ad for HARRISBURG INC. Main office was located in Fort Worth, TX. Valves Seal Positively Every Time. Buna-N synthetic rubbed molded to the wedge gate fits into the arms of the rubber inset, applying equal pressure to all sealing points. This unique 1959 old oilfield petroleum well industry magazine advertisement would display beautifully matted and framed. Nice graphics.