This unit is identical to Grohee relaxa. It will replace broken holder for any 28mm rails including Grohe relaxa.

it will also Fit to any rails with 28mm diameters. Next  size down is 25mm. and their is no other diameter greater than 28mm./ if you measure the rail and you find it  27, 29. 0r 30mm it means that you are not measuring it accurately however if you measure it close to 28mm its 28mm diameter rail you have and this unit will fit nicely

PLEASE NOTE THIS IS AN REPLACEMENT QUALITY PRODUCT TO FIT GROHEE BAR. 

ITS NOT ORIGINAL GORHE BUT WILL FIT PERFECTLY