Shielded needle unit with actuatable mounting feature

A needle unit comprising:

• a needle hub,
• a hollow needle mounted in the needle hub and having a pointed distal end protruding from the needle hub, the hollow needle defining a reference axis,
• a shield in which the needle hub is arranged fully or partly, the shield being axially moveable relative to the needle hub between an extended position in which the shield axially covers the needle distal end, and a retracted position in which the needle distal end protrudes from the shield, and
• coupling structure allowing the needle unit to be mounted on a drug delivery device, the coupling structure comprising:
• deflectable gripping fingers forming part of the needle hub and being adapted to grip a corresponding coupling structure on the drug delivery device corresponding to an initial mounting state, and
• blocking structure forming part of the shield and being adapted to block radial movement of the deflectable gripping fingers corresponding to a lock state,
• wherein the deflectable gripping fingers and the blocking structure are moveable relative to each other from an initial mounting position in which radial movement of the gripping fingers is possible, to an actuated lock position in which radial movement of the gripping fingers is blocked, this preventing the needle unit from being removed from the drug delivery device.