Liqui moly 3350 leak finder spray 400ml liqui moly 3350 p this leak finder spray 400ml from liqui moly is a leak test fluid for compressed air oxygen systems and cng gas vehicles once sprayed onto the surface it indicates where the leaks are by forming bubbles over them making it ideal for tanks pipework hoses screwed connections welded seams flange connections and fittings p p it can also be used for repair work on compressed air brake systems and air conditioning systems buse