Directions for use: 1. Unscrew the pen cap and use a soft cleaning head to clean the surface in a circular way. If the dirt becomes hard for too long, please breathe gently on the filter (or glass surface) and repeat the above operation. 2. Put the pen cap back on the cleaning tip after use, and rotate the pen cap half a circle. The rotating pen cap can supplement the required cleaning mat (cleaning material). 3. These can be used numerous times. It's basically a chisel tip sharpie with Cleaning fluid, Keep cap on when not in use ,Keep away from heat sources when using, such as lighters. 4. Electronic grade IPA excellent formula, will not penetrate or dry, stable and reliable, will not harm the instrument accessories, protect your machine. 5. Easy to carry, remove all kinds of stains at any time, good cleaning effect, low corrosion, often used to wipe dust, glue, ink, oil stains, fingerprints, stains and so on.