Sub-assembly for a medicament delivery device

A sub-assembly for a medicament delivery device configured to expel medicament from a medicament container, the sub-assembly comprising:

• a housing having a proximal end and a distal end;
• and
• a medicament container carrier extending along a longitudinal axis from a proximal end to a distal end, the medicament container carrier comprising a carrier wall having an open proximal end, at least one slot extending from the open proximal end in a distal direction, and at least a first leg portion and a second leg portion radially separated by the slot at least at the open proximal end such that the first and second leg portions are radially movable relative each other,
• wherein a first retaining structure extends from an inner surface of the housing, and a second retaining structure) extends from an outer surface of each one of the first and second leg portions at the open proximal end of the carrier wall, wherein the first retaining structure exerts a force on the second retaining structure at least in the circumferential direction to prevent the first and second leg portions from moving radially outwards.