The LENSPEN system is probably one of the most practical and effective systems I've tested to maintain its objectives. Small and lightweight, it fits easily into a pocket or camera bag. Its cleaning system is an impressive efficiency, provided you do not forget the small quarter turn before use (so read the instructions, it takes two seconds and avoids many questions). The brush ... I did not believe too much at first, but I soon discovered its usefulness to remove all those little dust shot into the grooves of the sun visor or around the front lens! Today I lost mine ... I bought one immediately, without asking questions.