AR-15 front sight post basics with flip-up BUIS

On a classic AR, the front sight post lives in a fixed F-marked base. On a rail-only carbine, the “front post” is part of a clamp-on flip-up unit. Ozark Armament’s FBUIS-B gives you that rail-mounted front (and a matching rear) in aircraft-grade aluminum.

View FBUIS-B on Amazon

What to get right with a flip-up front

• Seat the recoil lug in a Picatinny slot so the post cannot walk under recoil.
• Keep the post vertical when locked up; if the detent feels soft, reseat and retighten the clamp with the included hex driver.
• Elevation for zero is shared across the set’s dials—confirm which dial your particular unit uses for front vs rear before you chase groups.
• Fold clearance: the front must clear handguards, SCW braces, and optic packages when flat.

Kit facts

• Matched front and rear · spring-loaded · Picatinny · 3.84 oz
• Model FBUIS-B · ASIN B01AISP1KW · UPC 784672554763

Buy Ozark Armament Flip Up Iron Sights (FBUIS-B) on Amazon

Product facts from the public Amazon listing for ASIN B01AISP1KW only.