This Stainless Steel screw is to be installed “flush,” so you will need to create a concave shape on the shower-screen to seat it properly. Please see a video on how to do this here
NOTE: As this screw is further recessed than the original bolt-head screw, we recommend removing and cleaning the grouphead parts more often to prevent the screw from getting stuck.
For troubled and worn out groupheads we intentionally sell this screw to be longer (+2mm)