Disclosed is a teatcup liner adapted to be mounted in a shell to form a teatcup to be applied to a teat of an animal. The teatcup liner has an inner space with an upper head for receiving the teat and an outer side with a barrel. The barrel has an end portion on the outer side of which a primary engagement member is arranged. The primary engagement member is adapted to be in engagement with a secondary engagement member arranged on the shell. The primary engagement member is bendable relative to a length axis of the liner. A hindering member is arranged on the outer side of the teatcup liner on a side of the primary engagement member distant from the upper head so as to restrict bending of the primary engagement member away from the upper head whilst permitting bending of the primary engagement member towards the upper head. When the primary engagement member is engaged with the secondary engagement member, the primary engagement member is located intermediate the secondary member and the hindering member. Methods for mounting the teatcup liner in a shell are also disclosed.
