I've tried searching for this, but I don't know what it's actually called.

I'm looking for the circled piece in the following picture that allows you to mount a double stay rack to the front, using the fender hole.



If anyone knows what this thing is called, and where I can get one, please let me know.

+1 hopefully someone will answer

that looks like part of the rack to me, I'm not sure you can buy it separately.

If that's the Salsa Minimalist rack, then it comes with the rack (I think the adaptor is removable so the rack can be attached to this seatpost clamp). Maybe try contacting Salsa and letting on that you lost the piece and need a replacement?

Salsa is a QBP brand, ask at any shop with a QBP account.

You could make one in 10 minutes with a piece of aluminum flatstock.Bend it up,drill 3 holes and a couple bolts,done.

Just as Booger1 said, I made one for my bike last week so my front rack could be more stable. I actually got two door pieces (don't know what they are actually called), they are about three inches wide with two holes in it. I put one on top of the other with the holes aligned and put them on the brake mount (I have disc brakes, so no need for my mount).