Why do the 2700F series do not sit completely 100% flush?

below picture shows the spring cup of the stud installed in the upper panel.

The 2700F series are not sitting comletely flush when installed with the recommended panel preparation of 100° countersunk.  They stick 0,04mm out.

so: Yes, it will not be 100% flush but depending on the countersink angle it is in the worst condition a tenth of a millimeter.

countersunk 100° installation of 2700F series

countersunk 98° and 102° installation of 2700F series[/caption]

a larger hole will allow a flush fitting!
an 11.1 diameter hole +/-0.10 for the counter punched hole will do the job.