Winchester Ammunition Defender, 9MM, 147 Grain, PDX1, Bonded Jacketed Hollow Point, 20 Round Box S9MMPDB1 Engineered to maximize terminal ballistics as defined by FBI test protocol, PDX1 Defender ammunition provides maximum stopping power for the ultimate in personal defense. Winchester's innovative bonding process welds the jacket to lead core for improved penetration, 1.5x expansion and the proven performance you rely on when the stakes are high.