Hands down the best lightweight low-profile handguard out there. - Aero Precision AR15 ATLAS S-ONE M-LOK Handguard

This is a very well machined, well planned, well laid out, and ergonomic handguard for a very inexpensive price. It extends the flattop of your upper just enough to get an offset BUIS, your dot, and a multiplier on it. Front area, you got your BUIS again. Now if I need a flashlight... I can drop on a little mlok rail and go, but I'm not carrying 2 extra lbs of picitinny rail everywhere I go. Also in shaving the top rail down, you got a nice little size savings, and some good ergononics for a c-clamp hold on your rifle. Toss on an angled forgrip and some m-lok rail covers in your preferred flavor and you're good to go. You won't be tacti-cool with this one, but you will have a great rifle.