A Trac employee will be able to better answer your question, but no one services Koni but Koni. Wherever you take them, they will send them to Koni (i.e., they all send them to the same place). Also, I know you can order the Ground Control kit at TRAC since my friend Rob got his there, so I'm assuming you can also get ERS there since that's what comes in the GC kit.