The present invention relates to a medical device (1, 100) comprising a first container (10, 110) holding a first medium and defining a general axis, a second container (20, 120) holding a second medium, and fluid connection means (50, 150) for establishing fluid connection between the first container (10, 110) and the second container (20, 120), the fluid connection means (50, 150) being arranged at least partially between the first container (10, 110) and the second container (20, 120). The device further comprises a cover receiving portion (42, 42) and a cover (4, 104) removably mounted thereon to shield at least an operable portion of the first container (10, 110). The cover (4, 104) is operatively coupled with the fluid connection means (50, 150) and configured to cause a relative converging motion between at least one of the first container (10, 110) and the fluid connection means (50, 150) and the second container (20, 120) and the fluid connection means (50, 150) in response to a dismounting of the cover (4, 104) from the cover receiving portion (42, 142).
