Had a problem with a dripping shower. Shower doc was able to identify the shower from photos I emailed. Gave me options either to buy the shower cartridge £132 or purchase an overhaul kit £14 , which is seals ,washers and circlips, all that is required to do the job. They had video online linked to their website. Watch it a few times as it is done in "real time". It has tips and hints on problems that may occur when overhauling the shower cartridge. This was invaluable and recommend watching and following the advice. Think anybody could overhaul the cartridge if they take their time. I've waited a fortnight before writing the review,shower still working prefectly. Showerdoc service, advice, identification of the shower and delivery was second to none.