For getting the dust off the Pen Display 24, I suggest using the microfiber cloth that came with your Pen Display.
If there are smudges, you can use one of the products below to lightly spray on a microfiber cloth and gently wipe any smudges away.
Please know the Pen Display 24 is not a sealed device designed to withstand any moisture or outside elements in any way.
If you spill liquid onto the Pen Display 24, quickly unplug it and wipe it away using a microfiber cloth.
Never use ammonia-based cleaning products on the Pen Display 24 - ever. The ammonia can disfigure the surface of the Pen Display 24.
What do I use on my Pen Display 24? I have been using Screen Mom for years with my Displays and Camera Lens, and it works great.
Keep your Pen Display clean and free of dust. You will want to wipe down your Pen Display once a week or when you notice dust starting to gather on the surface. Xencelabs includes a micro-fiber cloth that is specifically designed to be used to keep your Pen Display free of dust.
If you are not using the glove to draw, you may need to use a display cleaner solution every once in a while to remove any smudges on your Pen Display. I have placed two recommended brands below.
You can find Screen Mom online; it is reasonably priced, and a bottle will last you for years.
Another excellent product is Sensei Optical Cleaning Spray. It is sold at B&H Photo Supply and is reasonably priced and effective.