Pres:Air:Trol TVA-211B Alternate Threaded Center Spout Air Switch
Tinytrol Air Sensor. Provides the same powerful switching action in a small package as found in larger air switches. Available in single pole or a very sensitive patented double pole design. DPDT, 21 amp, Latching, 9/16" thd.
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Presair Trol by Senasys
{"Item Package Dimensions L x W x H": "1.9 x 1.7 x 1.2 inches", "Package Weight": "2 Pounds", "Item Dimensions  LxWxH": "6 x 6 x 6 inches", "Brand Name": "Presair Trol by Senasys", "Part Number": "TVA-211B", "Date First Available": "January 12, 2016"}