Set of 12 fiber washers to protect battery terminals from corrosion. The washers fit both top and side battery terminals and cables. The size of the washers is flexible - the inner ring can be removed to fit larger terminals. The outer diameter of the washer is 1.73 inches and the inner diameter is 0.79 inches. After removing the inner ring, the diameter will be about 1.18 inches. The set consists of 6 red washers and 6 greenwashers. Color coding makes it easy to determine polarity - red for positive terminal, green for negative terminal.