The Super Pap Pen is mainly used for making hydrophobic barriers on glass slides for immunohistochemical procedures. The hydrophobic properties keep anti-sera or reagents in a confined area. This also allows the end-user to use small amounts of valuable anti serum or other reagents on the specimen. The green color will fade in alcohol or xylene. The hydrophobic barrier does not dissolve in alcohol, acetone or xylene, thus preventing contamination. Important Note: Do not put the barrier on the slide prior to deparaffinization and/or heat retrieval methods. The barrier will lose its hydrophobic properties.