Keeping a few extra factory magazines around is never a bad idea. Extra magazines save loading time at the range and also serve as a backup to your primary magazine when seconds count, and reloading is not an option.
*Separate sleeve required for use on the 509 Midsize or Compact not included.
UPC Code: 845737007775
Manufacturer: FN America
Manufacturer Part #: 20-100032-2
Fit: FN 509