I bought the adapter so I could change my stem. The adapter is thinner then the spacers on the the bike so when I remove one to put the adapter in I had to put in a generic ring that didn't match.

Easy solution for syncro headset which many will agree.
Also, superb service, fast and kind response on inquiries.
Only one thing I am not quiet sure is the product material.
I seems like some sort of plasitc and I am not sure it will hold, but time will tell I guess.