Example embodiments relate to an ear cup for use in a hearing protector unit including two ear cups, and a device to fasten the hearing protector unit to a wearer' s head, the device being connected to the ear cups. The ear cup may include a cup portion with a support surface； and a sealing device, placed against the support surface of the cup portion and intended to bear against a wearer' s head in an area around an ear of the wearer. The sealing device may include a sealing portion of a soft material, which includes a peripherally extending circumference slot and which, in its periphery area, bears against the support surface with an opening of the circumference slot directed towards the cup portion, a sound-attenuating ring, situated in the circumference slot of the sealing portion, and a clamping ring of a rigid material, situated in the circumference slot of the sealing portion to expand the sealing portion produced from soft material, the sealing portion being provided with a peripherally extending flange, introduced in the cup portion such that it bears against an inner side of the cup portion, whereby the clamping ring bears against the flange and presses the flange against the inner side of the cup portion for fastening the sealing device to the cup portion.
