@Peter167 there are potentially two types if you have full fibre and the cable goes to an Openreach ONT unit with lights you need an Ethernet cable with rj45 connecters. If however by the BT biox you mean an older phoneline master socket with no lights you require a DSL cable with rj11 connectors . Both can be found in most any hardware store or larger supermarket or online. The colour is not important.
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65inch Sky Glass, 3 Sky Streaming Pucks, Sky Ultrafast + and Sky SR213(white Wifi Max hub) main Wifi from 3 TP-Link Deco M4 units in access point mode
