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These were designed to compensate for the looseness and Flex inherent in the stock Tamiya M01-02 suspension parts. Printed in PA12 Nylon they are more durable and have no more play leaving you with a nice functional suspension instead of sloppy and loose.
The only items you need are a drill and a 3mm drill bit to open up the pivot areas to the correct diameter.
Better quality bits will most likely have better tolerances.
Video of installation and explanation.