An attachment device for connecting a fluid path set to a medical container includes a body having a pointed distal end configured for puncturing a membrane of the medical container and a proximal end configured for connecting to the fluid path set. The attachment device further includes a fluid channel extending along a longitudinal axis of the body between the distal end and the proximal end. The fluid channel is configured for delivering a medical fluid between the medical container and the fluid path set. At least one deflectable retaining element projects from the body of the attachment device between the distal end and the proximal end. The at least one retaining element is configured from non-removably retaining the attachment device with the medical container after the attachment device is connected to the medical container.
