"The Screwfix telephone extension kit beats the high street DIY kits hollow: better quality wiring (solid copper, not cheap stranded copper or poor quality metal). Better connections (IDC rather than screw terminals). You don't need scissors for opening the package and best of all, IT WORKS. And this quality actually cost less than the "gift wrapped" specimen from your local DIY."
"I have had this item operating perfectly well for over a year now. However when I installed it I had a lot of trouble getting it operating. This was eventually found to be due to bad soldering joints inside the socket. By this time the cable had been installed through a wall (with much effort to get it through the wall gap) so rather than dismantle and return the item, I re-soldered all the joints in situ.
My reliability rating is determined by the initial faults. Otherwise it merits a five because it has given faultless service since.
My advice - have a close look at the solder joints before you install.
WRT the poor instructions, there are plenty of instructions for installing these sort of things on the web. Mind you, this should not let Screwfix off the hook."
"The instructions don't tell you which wires go where! In my kit, there were red, yellow, black and green wires, but the instructions referred to 'green with white ring', 'blue', 'orange', 'white with green ring', 'white with blue line', 'white with orange line'. After some time-wasting research I managed to identify which colour went to which connection. I'm really surprised that stuff like this gets through Screwfix quality control!"
"The socket plug on this set is wired normally (2,3,4,5, as yellow, green, red, black). However, if you follow the instructions provided for wiring the linebox, it doesn't work. If you look at the wiring inside the linebox, you find that the numbering of the pins doesn't match the numbering of the wiring sockets, but is reversed. As a consequence, the incoming wires need to be connected in opposite order to the way they are stated in the instructions, namely: 2. White with blue line 3. White with orange line 4. Orange 5. Blue. If you do this (after wasting half a day doing the diagnostics) the system works perfectly well, and is good value. But I wonder how many other sets there are out there where the lineboxes are incorrectly labelled internally, and where they consequently don't match up with the instructions."
"I found the same problem with this product as a previous buyer. When first installed the extension phone seemed to work ok but would not ring. Research on the web revealed that the "Ring" wire must be connected to terminal 3 in the line box. All connections were re-made and even the soldered joint in the line box re-soldered. The cable was then continuity tested end to end. It was then discoved that the pre-made plug (as supplied in the kit) was wired incorrectly. Also the joints were poorly soldered. Once the Orange/White & White/Orange wires were reversed a simple (none powered) phone would now work ok but a Answer Style (powered Phone) once plugged-in just rang continuously. It wasn't until the other two wires (Blue/White & White/Blue) wires were reversed that all types of phones worked properly. This effort cost a whole day to sort out!"