A bottle teat comprising:A nipple sleeve having a hollow nipple and a through-hole connected at the bottom to a hollow nipple sleeve which is connected at the bottom to a nipple flange that is connected to the nipple sleeve to be fastened to a bottle by a fastening ring which serves at the bottom with an annular disc-shaped ring flange overlapping the nipple flange,A contact area projecting downward or upward from the nipple flange, or from the nipple sleeve above the nipple flange outward into the area for placing a ring flange, andA lip valve that is opened when the nipple flange is not fastened to a bottle arranged in a deforming area next to the contact area so that the deformation of the nipple flange that arises from pressing the fastening ring against the contact area closes the valve.
