The term 'Reversible' refers to the Fluid tip, or to put it more simply, the exiting orifice that is where the atomisation of the paint takes place. on some set ups, these tips are set into tip holders that allow you to rotate the tip should it get blocked by particulate matter or debris in the paint. You can reverse the tip using an external handle, press the trigger and reverse flush the debris out of the tip. You then rotate the tip back to its working position and start spraying again. See its really simple to understand, I suppose its a lot harder to translate to a foreign language.

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