to guide a yarn plug consists preferentially of a ceramic material however metallic hard chrome layers or carbon compounds are also possible thus cylindrical body 18 may also be manufactured from an aluminum material which receives an aluminum oxide coating forming friction surface 14 elongated slots 34 extend at least over a portion of cylindrical body 18 the second section 7 2 of the stuffer box is formed by enclosed chamber wall 15 that comprises plug channel 33 plug channel 33 forms at its end plug outlet 6 on the side facing yarn plug 13 enclosed chamber wall 15 comprises contact surface 20 that also carries wear resistant coating 35 formed out of two opposing rollers conveying device 29 is attached directly to stuffer box 2 at plug outlet 6 conveying device 29 guides the yarn plug 13 to a cooling device 30 arranged downstream from conveying device 29 cooling device 30 could be constructed from a cooling barrel on whose circumference the yarn plug is cooled both conveying device 29 and cooling device 30 are furnished with a coating on their contact surfaces 37 and 38 the function of the embodiment depicted in fig2 is essentially identical to the previous embodiment according to fig1 so that depicting the yarn course was not repeated however yarn plug development can be also influenced by conveying device.