Convert or replace your current P320 21 round 9mm magazine, or the 18 round .40 S&W / 357 Sig Magazine floorplate
THESE DO NOT WORK ON THE COMPACT, OR REGULAR FULLSIZE MAGAZINES THESE ARE ONLY FOR THE LONGER MAGAZINES.
**THESE DO NOT ADD OR CHANGE CAPACITY THIS IS JUST A REPLACEMENT PART**
*Only compatible with current 21 (9mm) round or 18 (.40 S&W/ 357 SIG) round magazines*