H2O Jet's High Pressure Cylinders last longer because they are made with a unique production process resulting in longer performance - it nearly eliminates cracking. Threads are pre-coated to help reduce galling (blue anti-seize is still requred!)
Please note: The Extreme Flow (EF) version is for the H2O Jet special, larger intensifier. It puts out 1.5gpm from a single intensifier.