English: Inner part of an adrenaline autoinjector.

1- Four latch mechanisms that hold the plunger secure 2- The loaded spring that drives the plunger and the needle (toward the right) 3- The plunger 4- Adrenaline solution 5- Outer body. When retracted upward (left) exposes the needle and triggers the latch mechanism. Later springs back to cover the needle after use

6- Needle exits through a protective barrier when this is pressed against the skin