Have replaced old bath with new shower and so far so good. The shower mixer unit is a Grohe Grotherm 1000 and is of the horizontal type. The unit uses S type connectors to connect from the unit to the rising pipework. I am trying to connect these to a 1/2 inch/15mm 90 deg angle brass fitting. Problem is that when I screw the S connectors into the 1/2 inch side of the brass fitting and tighten them they do so a differing levels. Does anyone know what i'm talking about and can help?