A medicament delivery device configured to provide a variable single dose of medicament is disclosed. The medicament delivery device includes a main body and a syringe arranged in the main body, where the syringe comprises a medicament. The medicament delivery device further includes a delivery member shield unit slidably arranged in the main body and a removable cap releasably coupled to the delivery member shield unit. The medicament delivery device also includes a dose knob configured to rotate with respect to the main body for setting a dose of the medicament. Prior to a dose of the medicament being set, the delivery member shield unit and the removable cap are axially locked with respect to the main body. Further, after a dose of the medicament is set, the delivery member shield unit and the removable cap are axially moveable with respect to the main body.