Ever since the addition of droop screws to the 1/8 scale market, there has been 1 basic flaw. For the manufacturers of the screw it was simply adding the 2 mm hex in the end. The larger hex on the button head end was left in the process. The larger hex unfortunately adds a cutting edge to the screw which we all have seen on our chassis. Also the more rounded end of a standard button head screw gives less contact on the chassis and acts more like a knife edge. The other alternative is to use a 4 mm set screw. This of course gives a much smaller contact patch and wears much quicker. My design has a flatter dome on the head.
This droop screw is designed to fit arms that use 4mm droop screws.