Delavan 5830-301C PowerFLO Electric Diaphragm Pump (On/Off Switch)Delavan PowerFLO Electric Diaphragm Pump (Image shown may not match exactly) Model: 5830 301C 12 VDC Automatic Demand with On Off Switch Delavan designs, engineers and manufactures a wide variety of electric pumps for many different applications. The 5830 series are 12 VDC or 115VAC and are also available in both Automatic Demand and Bypass versions. Pumps are manufactured with Viton valves and Santoprene diaphragm for increased corrosion resistance.