Dciltin, yea actually bought it from KKM before glockstore was offering them. Their website said they were drop in but It wasn't even close. Had to bring it to get shaved and sized, while at the smith I had brought a lone wolf barrel that I for a while but never shot. The lone wolf fit but had wiggle room(you could see the top of the chamber move left to right, my smith told me at the very least it would ruin my gun. Love the KKM haven't gone back since I put it in. Pain to have to get it sized but worth the hassle regardless.