The RAM-B-252 marine grade aluminum base consists of a 1" diameter ball and 2.25" x 0.875" base with 11mm hole. This part is often used on motorcycles, attaching to the mirror stem. This part fits well on many handlebar pinch-bolts with a washer (base is 5mm thick).
We've gone "ala carte" with most of our RAM pieces, build your mount however you want it! Please let me (firstname.lastname@example.org) know if there's something you'd like that isn't listed, or if you have questions about how to build your personal mount.
RAM Mounts 11MM Mirror Mount
Produced by RAM Mounts of USA