The gas source is environmentally friendly and free of oil pollutionNo piston design, strong continuous working abilityThe pressure can be adjustedThe pressure output is stableSmall size, easy to carryColour: greenMaterial: ABSSize: 15 x 5 x 5cmPackage Contents:1 x oxygen injector1 x USB charging cable1 x English manualOnly the above package content, other products are not included.Note: Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.