Needle-based injection systems for medical use (Insulin pen) must abide by ISO11608-1, it has replaceable container, each container holds multiple doses, the size of which is fixed.

The container holder allow visibility of the deliverable volume. The injection system requires the user to pre-set the dose, the injector provides an indication of the dose that has been set. It indicates the amount of medicinal product delivered, and indicates the amount of medicinal product not delivered.

The insulin pen is designed to function with it's specified needles and containers. 

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