Description Specifications Description The Haskel EXT420-2 is a pneumatically driven two stage, double acting R600 butane extraction pump. EXT-420-2 high-pressure, positive-displacement two stage piston pumps are safe, proven, reliable, and energy saving butane / propane extraction pumps. The high-pressure pumps offer the flexibility to speed completely variable from zero to maximum lbs/minute. No need for unloaders or bypass valves, simply add gauges and hoses to suit your application. Switchable between single and two-stage mode by turning a valve Use single stage mode for most of the transfer - when the inlet pressure starts to drop - switch to two-stage mode to pull vacuum as your process requires In single stage mode - the pump has identical performance to EXT420 Two stage mode allows the pump to draw vacuum down to 23-in. Hg State of California Proposition 65 WARNINGCancer and Reproductive Harm - www.P65Warnings.ca.gov. Product Specifications Pump Ratio4:1 Pump Displacement per Cycle20 cu. in. Drive Size5 ¾ in.Max Outlet Pressure1250 PSISealsVitonWetted Section MetalsStainless Steel Literature & Docs Accessories