Good for billet upper - Sharps Bros. Full Top Rail M-LOK Handguard

This handguard is unique because it’s anti-rotation tabs will still work with a billet upper (mine is from 360 Precision). They interface with the flats on the sides of the picatinny rail instead of the sides of the receiver body. When mine came it was missing the barrel nut, but I messaged sharps bros and they had me one in like 2 days (with a bunch of cool stickers). Another clever feature is that these barrel nuts work with a castle nut wrench. Absolutely top notch customer service and products! My lower is their livewire and it’s very nice as well. Zero complaints about this handguard. It’s stylish, light, solid, and has everything you need and nothing you don’t.