ProMag SIGA20 9mm Luger 21rd Blued Steel Magazine for Sig Sauer P320

The ProMag SIGA20 is a high-capacity 9mm Luger pistol magazine built as a dependable spare or replacement for the Sig Sauer P320 family of handguns. Manufactured by ProMag, this Standard model delivers an extended 21-round capacity for range, training, and defensive use.

The magazine body is constructed of heat-treated steel with a blued (black oxide) finish for corrosion resistance and long service life, paired with an injection-molded polymer follower for smooth, reliable feeding. The 21-round capacity gives the P320 operator substantially more rounds on tap compared to standard factory magazine offerings, making it well suited for extended range sessions and high-round-count training days.

The SIGA20 is designed to fit the Sig Sauer P320 9mm pistol and is also compatible with the Sig Sauer P250 9mm and Oracle Arms 2311. It seats securely for dependable performance in duty, competition, or recreational shooting applications.