Leica is known for their glass clarity. When I was a photographer I often mounted Leica glass on my Canon cameras when I needed absolute crystal clear images and colors. I think they will be in for a rude awakening when the units start flowing back in for repair after a death on a Glock or other pistol slide. Made in Portugal and priced at $599.
https://www.thefirearmblog.com/blog/2018/04/18/leica-tempus-red-dot-sight/
https://www.thefirearmblog.com/blog/2018/04/18/leica-tempus-red-dot-sight/