I just bought a used Czechmate about a month ago, after wanting one for years. There are a few things I don't really like about the stock Czechmate, including the huge C-More Slide Ride optic. It covers most of the slide, and doesn't allow you to mount other optics that have more readily available, easier to change batteries too. That's where this aftermarket optic mount helps immensely. I already had a Leupold Deltapoint Pro optic, and it was easy to figure out which posts to use and which screw holes, and I like that optic way better now. The only down side with this aftermarket optic mount is that the right side interferes just slightly with the slide racker, if it's installed all the way pushed in. It won't let you remove the slide, but it lets the slide function normally. I just pulled out the slide racker a little bit, and now it clears the optic mount. I'm looking forward to trying open division at USPSA for the first time this weekend.