and allows a pneumatic threading of the yarn 14 through the entire steam setting device 1 wherein when thread guide tubes 25 are used as yarn sluices 23 a and 23 b the latter firstly have to be removed before the threading of the yarn fig2 shows a perspective view of a first possible embodiment of a receiving element 26 which is used to keep six of the respective yarn sluices 23 ready which are configured as thread guide tubes 25 the receiving element 26 manufactured for example from a plastics material configured in the manner of a revolver magazine and shown in the present embodiment preferably has a central bearing opening 27 as well as six radially arranged bearing webs 28 the bearing webs 28 each being equipped at the end with an outwardly open sliding guide body 30 in which the thread guide tubes 25 are mounted axially displaceably and secured by attachment pieces 31 the thread guide tubes 25 may have different inside widths a two opposing thread guide tubes 25 in each case having the same inside width a in an advantageous embodiment this means that two of the respective thread guide tubes 25 are matched to a specific yarn diameter d with regard to their inside width a and can simultaneously be positioned in the yarn inlet opening 2 or in the yarn outlet opening 3 of the yarn treatment chamber 21 the attachment piece 31 is matched with regard to its dimension to a receiver 32 shown schematically in fig5 and shown in section in fig1 a and arranged in the region of the yarn inlet opening 2 or the yarn outlet opening 3 of the yarn treatment chamber.