The ACOGs are internallyadjustable compact telescopic sights with Tritiumilluminated reticle patterns for use in low light or at night. Bindon Aiming Concept BAC models feature bright daytime reticles using fiber optics which collect ambient light. The ACOG combines traditional precise distance marksmanship with closein aiming speed. Designed for use with the M16 family every feature of its mechanical and optical design was chosen for a single purpose to provide increased hit potential in all lighting conditions without failure prone batteries.