An injection device for injecting a substance from an ampoule inserted in the device, the device including one or more of the following components: an internal thread for engaging a threaded rod, the internal thread including several contact faces enabling the use of a different threaded rods, a real-time display for displaying a quantity of a substance, e.g., the quantity to be injected or dispensed, the quantity available for dispensing or the quantity dispensed, a mechanical lock for locking the device prior to inserting the ampoule, and a claw lock for preventing use of the injection device.