Underwood Xtreme Penetrator Features The Underwood Xtreme Penetrator uses a solid copper 140 grain bullet rather than a traditional lead-core jacketed design giving it a mechanically consistent structure that resists fragmentation on impact. This construction is built to punch through common barriers while maintaining forward momentum a priority for shooters who carry for personal or home defense. Because the projectile is a solid copper design it avoids the expansion inconsistency that can occur with traditional hollow point ammunition. Underwood builds this round for shooters who prioritize penetration performance in their defensive ammunition choice. Each cartridge is loaded to Underwood s demanding internal standards giving shooters confidence that every round in the box performs to the same specification. The 20-round box is sized appropriately for carry ammunition letting shooters rotate a fresh supply through their defensive pistol without excess waste. Underwood has built a reputation among defensive shooters for producing ammunition that pushes performance beyond typical factory offerings. For .40 S&W shooters who want a specialized penetrator load for personal protection the Xtreme Penetrator delivers a dependable purpose-built option. Underwood Ammo Xtreme Penetrator Specifications Brand: Underwood Ammo Model: Xtreme Penetrator Caliber: .40 SW Bullet Type: Copper Solid Bullet Weight: 140 gr Rounds Per Box: 20 Available At: GrabAGun