Unless you like using a flat washer then a split ring locking one every time you bolt something important to your car, these will be your best friend. On average one advanced car setup will use at least 20 of these locknuts. They have a small nylon/plastic ring in the tip of them that allow them to not vibrate loose when racing. Although, if you’re constantly removing them and installing them the nylon/plastic will wear out and these can loosen, so always check your hardware before racing.
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