Trijicon TR24g LVPO 1-4X Green Triangle Post with Switchview SV1540 Throw Lever and flip cap on a Aero ultralight scope mount.

Widely considered to have one of the best, most forgiving 1x eye boxes on the market. It excels at "both-eyes-open" shooting at close range, functioning much like a red dot.

AR-15 in images is for display purposes only