It is contains 8 sizes copper washers. Made of copper. M6 x 10 x 1 mm, 30 pieces. M8 x 12 x 1 mm, 20 pieces. M10 x 14 x 1 mm, 15 pieces. M12 x 18 x 1 mm, 15 pieces. M14 x 20 x 1.5 mm, 15 pieces.
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