PAC BB-1PR Pair of Bass Blocker/Passive Crossover Easily handles power of up to 50 watts Blue color coded leads for easy identification Encased in heat shrink tubing with wire leads for easy installation Pair of bass blockers Used for removing bass from speakers to prevent damage Frequencies blocked: 4 ohms: 0-300 Hz / 8 ohms: 0-150 Hz Filters out unwanted frequencies sent to the speakers Passive crossover designed for 6" x 9" speakers