It is used as a washer of a cowling screw (dish cap) to hold the exterior (cowl) of the motorcycle.
On 2017-03-13 14:37:18
I did not know that there was a black stainless steel dish cap. An ordinary rosette washer to be combined with this is a silver series, it does not match with black. However, this rosette washer is perfect in black. I use it to clip the black exterior of the motorbike. I am satisfied.