Here's what it looks like on my 16" AR upper with TBAC 30P-1.
STAY AWAY FROM DBMG INC!!
This was before TBAC was recommending TROS if you needed an adapter. The first one had burrs and didn't have a relief cut so it didn't seat on my barrel correctly. The replacement adapter looked like complete dog shit. I tried calling and emailing the owner several times before I got a response and he said send it in for a refund. After sending it back it took several more days of emailing asking about my check but got no response so in the end I was out of $60.