Features:1. Use PC Headset with most VOIP phones that have a RJ9 headset jack (Not compatible with RJ11).2. Adapter cable with 3.5mm Headset jack to RJ9 Desk Phones Jack for , and more.3. Don't need to worry about the compatibility. 3 kinds of converters of different standard inside to fit most brand.4. Convert 3.5mm plugs to 4P4C RJ9/RJ10 headset plug, you can use your own headphone to chat on telephone with this cable.Specification:Connector 1: RJ9 maleConnector 2: 3.5mm TRRS femaleCable length: approx 40cm/15.74 inchColor: picture colorMaterial: pvcPackage Contents:1 X 3.5mm Female Jack to 4P4C RJ9 Male Cable3 X RJ9 Male to Female Converter Cable (different standard)Only the above package content, other products are not included.Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.