The EXPS3-4 has been developed to optimize the functionality of the HWS. The buttons have been moved from the back to the left side for instant access, allowing a magnifier, night vision, or a back up iron sight to fit closely to the HWS body. This new button position allows the user to operate the HWS function switches easier than ever before. The battle tested circle/dot reticle will be offered along with a series of 1 MOA aiming dots that are vertically aligned and calibrated specifically for the ballistic drop of .223 caliber ammunition. The reticle provides 4 aiming dots for target distances of 0-300m, 400m, 500m, and 600m. The use of a magnifier is strongly recommended. - Single transverse 123 battery to reduce sight length- Ballistic reticle specific to .223 caliber munitions- Compatible with Gen I-III+ Night Vision Systems (tandem operation)- Shortened base only requires at most 2 3/4 inch of rail space - Battery cap and latch are eliminated and replaced with a simple O-ring, tethered cap; better sealing is achieved- Battery compartment is now separated from the base to allow it to hover over the delta ring of the rifle- Average battery life at brightness level 12 is roughly 500-600 hours- Side buttons, NV compatible with a single quick detach throw lever.