Patent attributes
A drug delivery device may include a housing defining a longitudinal axis and having an opening and a drug storage container including a delivery member having an insertion end configured to extend at least partially through the opening during a delivery state. The device may also include plunger moveable toward the distal end of the drug storage container to expel a drug from the drug storage container through the delivery member, the plunger including a body portion having an inner wall defining an axial chamber and an outer wall cooperating with the inner wall to define a body thickness. The device may further include a plunger biasing member disposed at least partially within the axial chamber, the plunger biasing member configured to urge the plunger toward the distal end of the drug storage container.