An injection device assembly includes a dispensing chamber housing and a plunger. The dispensing chamber housing is coupled to a needle. The dispensing chamber housing has an inner surface and an outer surface. The inner surface partially defines a dispensing chamber for holding a quantity of a substance. A dosage of a substance is cast into the dispensing chamber housing or cast onto a plunger that is inserted into the dispensing chamber housing.
1. A dosing assembly comprising:
a plunger having a top and bottom surface;
a removable, hinged sleeve having an interior and exterior surface, the sleeve fitting over the top surface of the plunger, the interior surface forming a mold into which a substance is cast onto the top surface of the plunger; and
the cast substance located on the top surface of the plunger.
2. The dosing assembly of claim 1 wherein the top surface of the plunger is in the form of a shape suitable for receiving the cast substance.
3. The dosing assembly of claim 1 wherein the top surface of the plunger has a texture.
4. The dosing assembly of claim 1 wherein the interior surface of the sleeve is coated.