Controlled Expansion & Weight Retention For Outstanding Stopping Power The choice of law enforcement agencies nationwide, Federal's unique Hydra-Shok jacketed hollow point bullet delivers controlled expansion and efficient energy transfer to penetrate barriers while retaining stopping power. The deep penetration of the Hydra-Shok bullet satisfies even the FBI's stringent testing requirements. On impact, the notched jacket hydrostatically ruptures along designated fault lines and mushrooms until the hardened center post base stops the expansion, leaving almost 100% of the bullet's weight in the target. If you hit what you're aiming at, this bullet will do it Mfg: Federal