The invention is directed to a cover (2) for a tap of a gas cylinder, said cover (2) comprising a shell (4) for housing the tap, said shell comprising a front area for an indicator, a wheel (14) for adjusting the outlet pressure and/or flow rate, and/or at least one outlet connector (12) of the tap. The front area of the shell is a part (43) that is distinct from, and configured to be attached to, the rest (41) of the shell (4).