made to be slightly elastic and flexible relative to one another the bottle holders 5 a 5 b and the channels 6 a 6 b are thereby in a row as can be seen from fig1 and 2 as a result of the channels 6 a 6 b a supply bottle v already connected with a supply tube which is not depicted can be introduced laterally into the bottle support 1 and inserted into the bottle holder 5 a or 5 b the channels 6 a 6 b are therefore used for conducting through the supply tube a linear shaft 9 is formed in the shape of a recess in the main body 2 in the area of the second arm 8 the shaft 9 hereby intersects the border areas of the bottle holders 5 a 5 b and is at least partially opened toward them furthermore a guide bar 10 is located in the shaft 9 on an outer wall in particular in the bottom it extends more or less over the complete length of the shaft 9 in the shaft 9 moreover a lateral first stop surface 11 a and a front second stop surface 11 b are provided on its underside not depicted the tension slide 4 has a groove corresponding to the guide bar 10 laterally a first projection 12 and a second projection 13 are formed on the tension.