I'm on a boat!
If you care to know more about me and why this site even exists...
You're probably here because you're interested in the harness you need to add the turn signals integrated into the door mirrors found on the 2015+ STI.
Check out the product page for more information. I can supply you with the wiring you need to do a clean, straightforward installation.
Once you have the harness, you can follow the instructions on the mods page to install your turn signals!