Strike Industries SPBUS Polymer Backup Sights Black Folding for AR-15

The Strike Industries SPBUS (Strike Polymer Backup Sights) deliver an affordable, low-profile back-up iron sight system for the AR-15 platform. Built around durable SI Polymer Extreme with a steel mounting tab and steel insert, the SPBUS is designed to handle real-world wear without piling unnecessary weight onto your rifle.

When flipped down, the rear sight doubles as a set of built-in secondary apertures, giving you a backup aiming reference even with a primary optic deployed. The low-profile, low-snag design keeps the sight tucked close to the rail, and both windage and elevation are adjusted tool-lessly by hand - no special wrench or coin required.

The rear sight features dual apertures: a larger 4.70mm (0.19") aperture for longer eye relief, low-light conditions, and faster target acquisition, paired with a smaller 1.75mm (0.07") aperture for more precise aiming. A spring-loaded folding mechanism snaps the sight up into a locked, upright position with positive engagement.

Finished in black and built for AR-platform rifles, the Strike Industries SPBUS is a budget-friendly BUIS that does not cut corners on the features shooters actually use.