Walker Push-to-Signal handsets allow the user to initiate special phone functions such as switching to a 2-way radio. Our Push-to-Signal handsets are designed for durability, comfort, and reliability. The components used are of the highest quality, ensuring their ability to withstand the most demanding of conditions. All Walker products are backed with a two-year limited warranty and are manufactured in the United States. Walker Push-to-Signal handsets are backed by FAA Contracts. The PTS 500 6M handsets have a RJ11 jack and connect to standard 6-wire modular RJ11 cables.