The model number is for a heads up red dot sight for 12.7mm .50 Browning with a range knob for adjusting the impact range of the dot. They make red dot sights for 50-762-556 heavy and LMGs with range knobs to adjusting the red dot. DI Optical sold some 1000 of the DCL120s to the US military for use in Afghanistan back in the 2007s or so. Anyone use or heard of issues or how this sight worked on the Ma Deuce? Also interested in info on the DCL110 and DCL100s made for SAW and other LMGs in the two smaller calibers. Anyone ever use the DCL110 or DCL100? Recoil issues? Not seen one for sale in forever - any in private hands?