Wing nut with M10 metric thread.
Nut with a pair of wings to enable it to be turned without tools, used where frequent adjustments are needed or part removal can be made quickly at some later stage.
Metric threads are designated with a capital M plus an indication to their nominal outer diameter and their pitch:
This nut is M10 x 1.5 - which means the outside diameter of the male thread it fits onto is 10mm and the threads are 1.5mm apart (the most common thread pitch for M10).
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