M8 1.6 16 8.4. M4 0.8 9 4.3. M6 1.5 12 6.4. M5 1.0 10 5.3. M3 0.5 7 3.2. A Form A washer is a standard-size DIN 125A flat washer with a wide, flat, circular design used to evenly distribute the load of a bolt or nut, protect surfaces, and prevent fastener loosening.
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