The HE508T-RD X2 is a titanium, open reflex optical sight. The X2 Series optics feature two improvements. First is the addition of Lock Mode from our 2018-2019 LE optic models. Lock Mode, when activated, locks the buttons preventing inadvertent setting changes. Second, the buttons have been redesigned to compliment the Lock Mode by placing them lower and out of the way. Additional features include a Titanium housing, Super LED with up to 50k hours battery life, Solar Failsafe, Multi-Reticle System, and Shake Awake.