This AIM-O branded scope is a reproduction of the ACOG 4x32 from Trijicon (Advanced Combat Optical Gunsight). The particularity of this ACOG model is that it does not require the use of batteries, as its receiver is illuminated by a red fiber optic light pipe. The light will therefore automatically illuminate when light is present.
This version also comes standard with an RMR reflex viewfinder on top, which has a light sensor to adapt to the ambient light.
This ACOG AIM-O features a 4x zoom, anti-reflective, anti-buzz, anti-scratch coating and will mount very simply with two clamping screws on a standard 20mm Picatinny rail.