Description
The Ruger American Magazine Adapter is a factory black polymer sleeve (Ruger part 90640) that lets the 45 ACP 10-round magazines from the full-size Ruger American Pistol (90512) seat and function in the shorter Ruger American Pistol Compact frame. The adapter wraps the base of the longer full-size magazine so it locks up correctly in the Compact grip.
Molded from durable polymer with a black finish, this lightweight sleeve is shaped specifically to the .45 Auto magazine profile and the Compact magazine well. It does not increase round count on its own; it simply bridges the length difference between the full-size and Compact magazines so a single pool of 10-round .45 Auto magazines works across both pistols.
Designed for Ruger American Pistol Compact owners who also use the full-size model (or vice versa), the 90640 adapter is the factory-correct magazine sleeve for keeping one set of magazines compatible across both Ruger American Pistol variants.









