Yeah I didn't get the o-ring. I noticed buffer technologies makes the o-rings too. Everything I've seen BT make is usually a gimmick. If it has problems extracting why not just fix the damn thing right instead of putting a o-ring on it?I would have just put a whole bolt on it but I didn't see anything wrong with the rest of it. Once my money will allow i would like to get a parts kit with all the springs,firing pin and all the critical parts. Maybe get a butt stock with some storage and keep the parts in the butt stock. Then if i do have another failure every things there and I can repair it on the spot and not have to wait a week. Here is the one I ordered.I didn't know if the was a difference in colors of the inserts or not.
http://www.midwayusa.com/viewProduct...tNumber=745270