Flat locknuts or speednuts are clamping plates that act as nuts for Parker screws.
This mounting part, made of spring steel, is used when a thread is required, but cannot be tapped due to the thinness of the thread.
They are also used in various places on our classic Volkswagen. Mainly around plastic or hardboard parts, but they have also been used on thin sheet metal where it is not possible to tap the threads or weld the nuts.
Corrosion affects the nut. If a Parker screw that is too thick has been used, the correct screw will no longer fit. In either case, you will need to replace these nuts.
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