This is a Holosun Technologies Red Dot known as the 510C, model HS510C+HM3X Combo.
Since Holosun's inception in 2013" their main goal has been to bring cutting edge technology to the end user. Holosun continuously strives to improve and innovate by producing technology that makes sense and works!
Features:
Multilayer Coatings
Picatinny Mount
7075 T6 Aluminum