Cable Length: ~13.2cm. Casing of this RJ11 to BT Convertor is made of durable plastic material. Dimension: ~5.1(L) x 2.1(W) x 2.2(H)cm. Weight: 18g this RJ11 BT Adapter to convert one RJ11 socket to two BT sockets. It allows two telephones or modems with a UK plug to to a single RJ11 socket. This RJ11 to BT Adapter is very simple to . You just plug the adaptor into the RJ11 phone socket, and plug your BT cables (not supplied) into the adapotor, and thats it your done One end is 6P4C RJ11 plug and the other end is two 6P4C BT sockets. Package Included: 1 x RJ11 Plug to Dual BT Socket Adapter. Note:Light and different displays may the color of the item in the a little different from the real thing. The measurement allowed error is +/- 1-3cm.