In the "1911" world, there are, for fixed sights, essentially two standards, the original G.I./Colt dovetail, and the Novak low-mount dovetail.
For adjustable sights, while there are adjustables that will fit both of the fixed-sight dovetails, the most common for "target" style sights are Bo-Mar and LPA.
Probably 99% of the 1911s on the market, across all brands, have one of those four rear sight dovetails.