This replacement or spare magazine is compatible with your Sig Sauer P320. It is constructed of heat treated steel with injection molded mag follower and mag spring formed from chrome silicone wire. Made in the USA.
Specifications:

Caliber	9mm Luger
Capacity	32
Finish	Blued
Model	Sig P320
Material	Steel
Type	Detachable
Model Fit	P320
Brand Fit	Sig
Max Capacity	32