Cold-formed sheet steel profiles with a C-shaped cross-section in accordance with EN 14195 and corrosion protection C5M for use as a base or supporting profile for suspended AQUAPANEL® / Drystar ceilings. The corrosivity categories C3 and C5-M refer to the classification in accordance with DIN EN ISO 12944-2:1998-07 and DIN 55634-1:2018-03.