Uvital Phone Jack to Ethernet Adapter, RJ11 to RJ45 Adapter, RJ45 Female to RJ11 Male for Landline Telephone, with RJ45 to RJ11 Cable (Black,2 Pack): Amazon.co.uk: Electronics & Photo
Locking Waterproof CAT6 RJ45 Female to Female Lan Ethernet Network Extension Adapter Coupler : Amazon.co.uk: Electronics & Photo
Cat6 Ethernet Cable 25 Feet, Snagless Cat 6 (25ft to 300ft), RJ45 Patch UTP LAN Network High Speed Internet Cord with 15 Cable Ties and 1 RJ45 Coupler-Black 25 ft : Amazon.co.uk:
SEBSON 4x RJ45 Coupler Female to Female, LAN Connector, Extender Adapter for Ethernet Cable, Network Cable, Patch Cable: Amazon.co.uk: Computers & Accessories