Powerful compact pump . Hysteresis (often confused for Mag Drive) super wet rotor 66 GPH submersible pump features a stainless steel pump rod for super smooth operation. Contains no seals or messy oils. Pump employs the latest technology in hysterisis style pumps. For submersible operation only. Very powerful unit in a tiny size. Use 5\16" ID tubing , a normally stocked item at your local hardware store. Built-in flow control with unlimited settings. PERFORMANCE: A) 66 GPH @ 0 FT B) 55 GPH @ 0.7 FT C) 34 GPH @ 1.3 FT D) 11 GPH @ 1.9 FT E) 0 GPH @ 2.1 FT