The Fremco Cable Gasket, 8 mm (103-10207, Millennium part 513087) seals the blowing head around an 8 mm cable during a MultiFlow jetting run, holding air pressure in the duct so the cable rides the air stream instead of leaking pressure at the seal. Sold in packs of 6, it's sized specifically for 8 mm cable diameters run on Fremco blower platforms. Matching the gasket size to the cable is what keeps blow pressure consistent over long duct runs. Millennium stocks the full Fremco gasket range from small microduct sizes up through 23 mm for the same blowers.