not universal [SEP] i bought this after my deva trained curly specialist stylist used it on my hair it does not move the hair at all as it is drying keeping down the frizz slightly deep to dry more hair at a timebut sadly this does not fit my revlon perfect heat drier the driers end has a ridge at the last or so that is smaller than the rest of the nozzle that last inch fits but the rest does not so it will not stay on this diffuser requires that more than an inch of the drier be inserted as the rubberized treads inside that make it a flexible fit are located further down the barrel considering i do not have an unknown or rare brand drier this diffuser should probably not be called universal i considered buying the bio ionic drier to go with it but not at that price