Not all AR15 stuff is made the same way with the same concepts in mind. The Arisaka Defense MLOK mounts are the best in the industry, legitimately very happy with them. There's a vertical grip hiding under the Ferro MC-Black Slingster as well. The MTG 3 Slot M-LOK Rail Cover is one of my favorite cheap and easy to use rail cover. I use a Modlite OKW 18650 rechargeable setup on this rifle. It's bright and I am content with it's offensive capabilities. That's an old prototype Arisaka Defense tail cap on that Modlite which only has momentary on setting.