An adjustable hydrocephalus valve for pressure equalization of the cerebrospinal fluid in the cranium of a hydrocephalus patient. The valve is adjustable to change the opening and closing pressure of the valve. The valve housing has a cover portion that can be depressed to thereby disengage a locking device to permit adjustment of the valve. The cover portion bulges outwardly, but bulges inwardly when depressed. The cover portion snaps when moved between the outward bulge and the inward bulge to thereby generate an audio and/or visual signal indicating that the cover portion has been switched from the outward bulge to the inward bulge, and vice versa.
