ProMag magazines are designed utilizing both traditional stamping and welding of heat-treated high carbon steel, and modern precision injection molding of mil-spec polymer compounds. Every ProMag magazine is backed by a lifetime guarantee against manufacturer's defects. This ProMag Drum Magazine is constructed out of DuPont Zytel based polyer and the upper tower has full length steel internal insert stamped and welded like the factory magazine.

Specifications and Features:
21-round magazine
Sig Sauer P320 9mm Pistol
Magazine body constructed of heat treated steel with black oxide finish
Injection molded magazine follower
Magazine spring formed from heat treated chrome silicone wire
Steel
Blued with FDE Base plate
Made in the USA

Fits:
Sig Sauer P320 9mm Pistol