Review on Variety of Colored Fiberglass Scratch Brushes by Richard Payne

I've used this to clean electrical contacts with good results. From time to time, a timer, flashlight, or other battery-powered electronic device will not work properly even though the batteries are good. Wiping the battery contacts and posts with this brush for a few seconds will restore normal operation in most cases. This brush is good for large contacts, while the extra fine brush is good for small contacts and contacts in deep or hard-to-reach places. This brush is not very large, its diameter is about twice that of a very thin one.