LensPen is a Lens Cleaner that is quite small and ultra-light. It is pen-shaped and was designed to clean optical items like camera lenses, riflescopes, binoculars. It is now finally available for cleaning drones. The tip used for cleaning is to some extent concave, making it suitable for the lenses considering their convex shape.
When it is a discussion about clean optics, then LensPen is necessary to ensure camera lenses, sensors and filters are clean. Years back, people would clean windows and mirrors using newspapers. This is because they have printing ink made from a carbon compound, which in turn has a high ability to absorb oil and any other contaminants. The current products designed for cleaning drones have grey pens using the original LCF invisible carbon because carbon is responsible for cleaning. All of them come in polybags with a set of instructions on how to use them.