Keep your pool bacteria-free with the 4-pound Torpedo Pac. Simple to use and long-lasting, the 4 Pound Torpedo Pack is your ticket to worry-free and low maintenance pool ownership. The Pool Frog  Leap Torpedo Pac works slowly releasing a steady low volume flow of Chlorine into your pool. It is a self-contained and highly efficient method of adding Chlorine to your pool water.  Pre-filled with 4 lbs of trichlor. For use with the FROG® Leap® Twin®.