All nuts are A4 316 grade stainless steel for maximum corrosion resistance.
Some examples of the places each size are used on Sharks
M5 - Used on Bat QR base plates
M5 Nyloc - Used on USP rudders
M6 - General rigging nut
M6 Nyloc - Used on USP centre steer system
M12 - Used on classic pins
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