[Medicament delivery device] The present disclosure relates to a medicament delivery device (1) extending generally along a longitudinal axis (L), and having a proximal end configured to point towards a
dose delivery site and a distal end configured to point away from the
dose delivery site, the medicament delivery device (1) comprising: - a cassette (10) comprising a
syringe holder (13) for holding a
syringe (14) - a power pack (20) comprising a drive spring (25) a
plunger rod (24) to expel medicament from the
syringe (24) when driven proximally by the drive spring (25) - a distal button (22) wherein the syringe holder (13) comprises a least a leg (133) extending distally and having, at its distal end, a seat (133a) for a proximal part (242a) of a lever (242) of the
plunger rod (24) such that when the proximal part (242a) is received in the seat (133a), the
plunger rod (24) cannot move proximally relative to the syringe holder (13), wherein the button (22) comprises at least an arm (222) extending proximally and having, at its proximal end, a knob (222a) configured such that a proximal movement of the button (22) brings the knob (222a) into contact with a bottom surface (242b) of the lever (242), thereby lifting the proximal part (242a) of the lever (242) out of the seat (133a).