Feature: l The front view of the visible red fiber and the back view of the green fiber provide the brightest viewing point in low-light conditions l Folding thumb sliding mechanism, sliding spring loaded button can flip l The spring fold up view is easily activated by pulling the rear cover and can be folded by pressing down l Impact resistant polymer construction provides lightweight durability l Please pull out the screw before installation, then snap the screw into the groove of the guide rail. l Compatible with most Picatinny / Weaver orbits. Not applicable to natural gas blocks with tracks Specification: l Color: Black l Material: Nylon l Interface:for Picatinny / Weaver Rails Package: l 1x Front Nylon Sight l 1x Rear Nylon Sight l 1x Allen Wrench