EOTech is one of the most trusted manufacturer of military and civilian weapon sights and accessories, and the is the perfect example of why. The HHS I combines the popular EXPS3 with the innovative G33 3X magnifier and Switch-To-Side mount. Both of these units work seamlessly together and offer quick-detach, locking mounts. The EXPS3 is among the most compact units available requiring minimal rail mounting space. When combined with the G33 magnifier the entire HHS I units measure a mere 8.1" and requires only 2.75" of rail space for mounting. When faced with variable situations the HHS I is the ideal choice with the ability to quickly switch from 1x to 3x with the flip of a finger. The G33 is held in place with a strong detent that maintains its perfect alignment with the EXPS3, and hold the unit out of the operator's way in CQB situations. Perfect for any situation, the HHS I offers 20 illumination intensities, anti-glare coatings with high light gathering capability, true holographic transmission for a parallax free optic that features a true heads-up display for shooting with both eyes open. Additional features of the HH I are Night vision compatibility as well as a ballistic BDC reticle matched to .223 ammunition.