UNIVERSAL COMPATIBILITY – This RJ11 cord is compatible with ADSL router / modem, Xfinity/Comcast, Spectrum, AT&T, COX and Altice USA (Internet service provider) devices. SOFT & FLEXIBLE – RJ11 to BT cable is soft and flexible for ease of use and avoids the hassle of entanglement but remains strong to provide superior performance. QUALITY ASSURANCE – Internet broadband lead is approved by RoHS certificate. This Keple high speed telephones cable provides protection from bending and interference that can reduce the signal quality. EXTRA DURABLE – ADSL cable has fully molded strain relief and better shielding than most of other RJ11 extension cables. This RJ11 telephone extension cable molded connections improves durability and strength reducing the risk of cable and connector separation. HIGH SPEED – Keple flat RJ11 to RJ11 provides high-speed transmission and its faster than most of other modem extension cables.