RJ45 to BT431 is used to connect the. RJ45 to RJ11 uses 4 wires straight through (Pins 1-4 RJ11 to Pins 3-6 RJ45). 2 pair CAT5e BT Cables Ltd Solid Copper cable - White or Black. phone line from a BT socket to a CAT5e CAT6 patch panel.
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