M24 25.3mm 39.0mm 3.4mm. M12 13.0mm 19.5mm 2.5mm. M20 21.4mm 30.7mm 3.4mm. Wedge-locking washers positively lock the fastener in a joint which is subjected. Wedge-locking washers are recognised around the world for their ability to secure bolted joints, even whenexposed to severe vibration and dynamic loads.
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