A cylinder-and-piston assembly for a bottle attachment apparatus for handling liquids in which the stroke length of the piston of the cylinder-and-piston assembly is delimited by a stroke length stop when suctioning from the cylinder and is delimited by a readjustment stop when exhausting into the cylinder. The readjustment stop is disposed on the piston or on the cylinder housing and interacts with a fixed stop. The readjustment stop is accessible and adjustable by way of a removable seal. The seal is connected by way of ribs to a piston bearing. The readjustment stop is disposed below this removable seal. The seal has a molding and the piston bearing has a counter molding. Displacement of the seal in relation to the piston bearing moves the seal in the longitudinal direction, and by this movement, the seal is removed in a manner that preferably is not capable of re-assembly.