Amazing quality: fits better than a "glove". There's zero play, so be patient and don't "cockeye" it. Smooth and even (parallel to the slide) or slide in from the side and lower it into the place. Very light, but sturdy. Thin to be unobstructive; generous sights co-witnessing. Excellent hardware and a key (a keeper!). No play/shift. The only and minor "gripe": wish it was closer color match: it's a bit darker ("blacker") and glossier/shinier than the matte CZ finish. But it's so thin and fits well, it doesn't bother me.