Mako Universal Mount and Primary Arms Green Dot sight, the sight is no longer available, but just for your information these type of sights work great for bad eyes. I was having a hard time with my iron sights. This type of sight made shooting enjoyable again. Just put the dot and squeeze. Bought the sight on Amazon. Check out the pics in the link, shows the mount on other guns.
Amazon link: http://www.amazon.com/gp/customer-me...e=UTF8&index=0
The setup on an EAA Witness Match 9mm
Same setup on my M&P 22