Tight fit at first - IMI Defense Ergonomic Over Molded Magwell Grip w/ Integrated Enhanced Trigger Guard

The flared maxwell feature is OK but it's not going to be as smooth as a lower that was built with it in mind. It's a bit tricky getting it on as you have to line it up properly while also sliding it in from the bottom up. On my ar I had to forgo the push pin as there were no cut outs for it on the imi. Still holds on fine with just the roll pin but some might not like that.