if the cz 527 rail size is what you need. might i suggest a set of inexpensive tikka t3 factory rings that came with the t3's that most folk don't use. one of the rings will have a bolt stop but if you don't need it just punch it out. i used a set of the tikka t3 aluminum rings on a cz-527 american and have no complaints so far.
good luck,
Big Ed
