Overview Reviews Product Description ProMag Industries Magazine, 9MM, 21 Rounds, Fits Sig Sauer P320, Steel, Blued Finish SIG-A20 Product Videos Product Reviews Write a Review Write a Review × ProMag Industries PROMAG SIG P320 9MM 21RD BLUE STEEL Rating * Select Rating 1 star (worst) 2 stars 3 stars (average) 4 stars 5 stars (best) Name Email * Review Subject * Comments *