First, as requested, here's a picture of both revolvers, the 629 is on top with the 625-2 below.
Both sights are the same, the Holosun, green, HE507C. The sight offers a choice of three reticles, a 2MOA dot, a 32MOA circle or the dot and circle together. It has a memory and motion sensor which means, when turned on, it will return to the brightness and reticle you had when it was turned off. The motion sensor when activated will automatically turn the sight on whenever it is picked up or moved. It's ready to go the instant you pick your firearm up. It turns off automatically in a few minutes when sitting still. This is great because it gives you longer battery life if you forget to turn it off manually. I used a Weaver type Weigand mount on the 629 (.44 Mag.) which you can get from Weigand Machine and Design (
[email protected]). I used this mount because I may want to mount a scope on the 44 mag. in the future. The mount on the 625-2 (.45 ACP) is a Raptor (
[email protected]). I used it on that revolver due to it's low profile. The Holosun comes with a base to attach it to a weaver style mount. The base if easy to remove to screw the sight to the Raptor mount. I hope I covered everything to answer all your questions. Last, I should mention that yes, these sights are great for failing eyes!