The black phone detangler stops your coiled phone cord from becoming twisted and tangled. Rotates 360° as you do while you are talking on the phone to extend the life of your phone cord The telephone wire is for use between handset and telephone, RJ11 plug 4P4C, not from telephone to wall plug.
Note: Not applies to VOIP phone, not fit for RJ45 modular plug Easy to use, installs easily without the need for tools. Simply plug the detangler into the end of your handset, and plug the handset cord into the detangler on the other end, and now they are connected. Removal of the detangler is also very easy Extended coiled phone extension cord is good to long-distance communication for your desk phone or office phone. Suitable for AT&T, NEC, Rolm, ITT, and Tie family fixed telephone, fax and modems High quality gold-plated metal contacts phone line detangler fits most handsets especially with deep recessed jacks, you should give it a little spin, then you won't feel frustrated with entangled cord