Easy to use automatic injection gun made especially for small dose injections. Total volume of cylinder injection is only 1/2 of a CC. Can be adjusted down to 1/10 of a CC without leakage. Has convenient bottle holder screw-on mount to make it easier to load and unload vaccine bottles. This gun is designed to have an entire bottle of vaccine attached. The dosage amount is set via the screw dial at the top of the cylinder. Settings of 1/4, 1/3, 1/2 CC are much easier to achieve without the leakage of prior models, which were made for large dosages and larger animals. Ed Minvielle uses two of these, one for PMV and one for Salmonella. Keeps the vial of vaccine loaded on the gun and keeps in the refrigerator. Takes out as needed. Only need to replace needles between shooting. Best and most accurate way to vaccinate birds.