Diamond Back Tactical has lowered the price of the ELCAN M145 Optical Sight while supplies last... "The ELCAN M145 Optical Sight combines ELCAN’s legendary robustness and optical brilliance with a ballistically calibrated LED-illuminated ranging reticle. Designed for application on Machine Guns and M4 Carbines, it is in wide service with the United States Army (NSN 1240-01-411-6350) and has been proven to withstand the rigors of modern combat.