Noise Filter removes electromagnetic interference (EMI) up to 30 decibels, and improves transmission quality up to 9 times! 1 and 2 line versions (RJ-11, RJ-14). Use it on corded phones, modems, faxes and answering machines, too. It meets all FCC regulations. Install it between the wallplate and your phone cord.
Before You Order
Not recommended for cordless phones.