An injection device and an injection device trainer for training a user to use an injection device. Each one of the injection device and the injection device trainer can include: a body portion； an actuator positioned towards a proximal end of the body portion, the actuator moveable from a proximal position to a distal position； a shield positioned towards a distal end of the body portion, the shield moveable between: an initial position； an extended position that is more distal relative to the body portion than the initial position； and a connector that connects the actuator to the shield such that movement of the actuator from the distal position towards the proximal position pulls the shield from the extended position to the initial position.
