We do want you to know that K-COM Filters are in use worldwide, solving telephone interference. You might want to contact us first to discuss your particular situation. We may be able to offer information to help you solve the problem. There is interference on my wall phone. Usually there isn't room to plug a filter into the back of a wall-mounted phone.
Installation is simple and complete instructions are included.
I have been using a K-COM Filter with good results until yesterday. My phone went dead and when I removed the filter and plugged the line straight into the phone, the phone worked again. If your K-COM Filter ever fails for any reason, return it for free repair or replacement. Telephone Interference can disrupt normal operation of these devices. It's best to install it at the line input to the equipment.