This replacement or spare magazine is compatible with your Beretta Px4 Storm. It is also compatible with the Beretta Px4 Compact, Px4 Sub-Compact, and well insert/magazine release.
Specifications:

Caliber	9mm Luger
Capacity	15 rd
Finish	Black
Model	Px4 Storm
Material	Steel
Type	Detachable
Model Fit	Px4 Series
Brand Fit	Beretta
Max Capacity	15