With the tracer wafer installed in the TW Filter Drier, the days of handling liquid dyes, getting false leak indicators and long, tedious leak searches are gone! The tracer wafer is placed in with the desiccant. When the system is started, the lubricant dissolves and circulates it throughout the refrigerant. If there is a leak, the dye will leave a mark where the refrigerant is leaking. The exact point of the leak is visible by a UV flashlight and looking through fluorescence-enhancing safety glasses. After the repair, wipe the dye using Glow Away or similar cleaner.