Universal Valve Type 521DP 522DP Double Poppet Safety Valve OPW 12072

  For sale is a surplus Universal Valve Co. Type 521DP / 522DP
  Double Poppet Safety Valve.  (1) 1-7/8" Diameter external threaded
  end and (1) 1-7/8" diameter internal threaded end. Zinc plated,
  cast iron body and top.  Stainless steel spring, shaft and reset
  nut.	Buna-N seal.  NOTE:  These valves are believed to be unused /
  never installed.  Feel free to ask any relevant questions.

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