A hose device includes a hose portion (3), at least a first end portion (2) and a channel (5) which extends along the hose device (1) through the first end portion and the hose portion. The hose device has flexible and elastic properties. The first end portion (2) of the hose device is in a mounted state arranged to be attached to a tubular connection member (7) by having the connection member introduced in the channel (5). The hose device has a transition portion (4), which is located between the first end portion (2) and the hose portion (3). The channel (5) thus extends also through the transition portion and has, at the transition portion (4), in a non-mounted state a non-circular cross-sectional shape and in the mounted state a substantially circular cross-sectional shape, which permits a free liquid flow through the channel (5).