Durable Material: Our telephone adapter is made of durable plastic material for stable signal transmission and long service life Performance Function: Specially designed 2 way RJ11 6P4C Adapter Converter allows you to plug two telephone devices into one jack. Or two telephones or modems with plugs to be connected to one telephone socket Easy to Install: Installation is simple, you can manually install without any other installation tools. Just plug the adapter into the RJ11 phone socket and plug the RJ11 cable (not provided) into the adapter Multi Use: You can split a line between any two different telephone lines. This hit the spot. Suitable for all standard RJ11 equipment, such as fixed telephone, fax or answering machine, fixed telephone, office line, etc Package include: 2 PCS Telephone RJ11 2 Way Adapter Converter, RJ11 cable (not provided) into the adapter