This fastener was made for the radio control hobbyist that is looking for weight reduction as well as beauty. This can be used for many needs but was designed for mounting of the larger servos. The broach is special as well , we manufactured this with a larger broach ( 2MM ) for easier insertion and removal. When many servos are required in a plane,boat or race car this fastener will eliminate quite a bit of weigh.The flange/washer dimension is 7MM in diameter