What is the purpose of a braze-on on the underside of seat stay? I have a Jamis Citizen 2 Step through (2013 or 14 maybe) which has a braze-on on the underside of the seat stay near the brake studs. Just one braze on each side. I'm curious as to what the intent is and what opportunities they enable. I already mounted rack and fenders so I'm not talking about the brazes near the seat tube. In the photo behind the link look closely and see the braze-on just on the inside of the back wheel. Here is the bike: Photo: < Zoomed in photo highlighting the specific braze-on: !enter image description here

I'm not positive, but I believe those are for a **frame-mounted wheel lock**. These are locks that you mount to the frame in roughly that location that immobilize the rear wheel when locked. Typically they mount via the brake braze-ons or their own straps, but that location looks about right for a direct mount

An example of a fitted lock can be seen in this image:

!AXA lock on Jamis

This type of lock is convenient, but not especially secure, since a thief can always just pick up the bike and carry it off. Some do include a way to plug in a cable or chain in order to lock the bike up to something else, but those aren't especially secure, either.