RJ12 plugs fit all RJ11 sockets. Uses a special and expensive extended Shielded RJ12 plugs these are much stronger/better crimp so stop any chance of cable pull out due to the cable being strained at angles!
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Ethernet Cable Cat6 Lan Cable UTP RJ45 Network Patch Cable 1/5/10/20/30M For PS PC Internet Modem Router Cat 6 Cable Ethernet
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RJ12 is backward compatible with RJ11. Top Quality Cat5e Solid Copper Network Cable made by Excel or Connectix etc.
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Vention Ethernet Cable Cat6 Lan Cable UTP RJ45 Network Patch Cable 10m 50m For PS PC Internet Modem Router Cat 6 Cable Ethernet
Aliexpress UK
The BT VDSL filtered face plate will take the bigger RJ45 plug. Uses a special and expensive extended Shielded RJ11 plug these are much stronger/better crimp so stop any chance of cable pull out due to the cable being strained at angles!
eBay
Vention Cat6A Ethernet Cable 10Gbps Lan Cable UTP RJ 45 Slim Ethernet Patch Cable Compatible Patch Cord for Modem Router
Aliexpress UK
Uses a special and expensive extended Shielded RJ12 plugs that are stronger and correctly crimped onto the the outer sheath of the cable. Top Quality Cat6a stranded shielded Copper Network Cable made by Excel.
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Cat6A Ethernet Cable 10Gbps Slim Lan Cable UTP Network Patch Cable For PS PC Internet Modem Router Cat 6a Cable Ethernet
Aliexpress UK
Works well, haven't needed it since moving house.
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Vention Ethernet Cable Cat6 Lan Cable UTP RJ45 Network Patch Cable 40m 5m 2M For PS PC Internet Modem Router Cat6 Cable Ethernet
Aliexpress UK
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CAT8 Ethernet Cable RJ45 Flat Internet Network Cable RJ45 Patch Cord LAN 0.1M 0.2M 0.3M 50M for Router Modem Cable Ethernet Cat8
Aliexpress UK
RJ12 Plugs fit all RJ11 Sockets. Top Quality Cat6a stranded shielded Copper Network Cable made by Excel or Connetix etc. if not anywhere else. You cannot call any 'Copper clad aluminium' cable a Category cable or patch lead, as this is an industry technical reference that belongs to the USA TIA and the ISO International Standards Committees.
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CAT6 Ethernet Cable Network Cable Patch Cord Black Round RJ45 for PC Laptop Modem Router TVs Home Office 50m 30m 10m Cat6 Cable
Aliexpress UK
The BT VDSL filtered face plate will take the bigger RJ45 plug. Top Quality Cat6a stranded shielded Copper Network Cable made by Excel. (this is more flexible, I doubt I will be making these with solid cable ever, it will not fit the plugs).
eBay
Cat7 Flat Cable Ethernet Cat 7 10/5/3/2/1.5/1/0.5m RJ45 Network Cable Cat7 Patch Cord for Router Modem 10Gbps RJ 45 Lan Cable
Aliexpress UK