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+1 for EPDM. It's a fifth of the price of EK's ZMT and just as much a pain to fit. Found matte black with no markings on that auction site, sent as one length.Mayhems if you want clear, EPDM tube if you want to just leave it. EK's ZMT is probably easiest to get hold of, but Alphacool and Watercool also do 13/10 EPDM. You can, of course, get EPDM tube anywhere, but it's tricky to find PC watercooling sizes and also without external markings.