Accurately orient and annotate your autoradiography films with the innovative Glow Writer™ Pen. This unique marking pen uses a special phosphorescent ink to create markings that expose directly onto X-ray film, serving as a safe and effective non-radioactive substitute for radioactive inks. Simply write on your gel, blot, or filter, expose it to bright light to charge the ink, and the glowing markings will transfer clearly to your film, providing an essential reference for analysis. Key Features & Benefits Safe, Non-Radioactive Marking: Provides a reliable method for marking films without the hazards associated with radioactive isotopes. Exposes Directly onto Film: The phosphorescent ink is excited by light and then emits its own light, creating a clear image of your writing on the X-ray film. Optimized Afterglow: The ink is specially formulated to have an afterglow half-life that is perfect for most standard exposure times, ensuring your markings are visible but do not overexpose the film. Fine Point for Precision: The fine point nib allows for clear, precise, and detailed writing, ensuring that even small annotations are easy to read. Replaceable Nibs: The pen features replaceable nibs (sold separately), extending the life of the pen if a tip becomes dry or damaged.