A drive assembly 1 for use in a drug delivery device comprising a housing 2 having a proximal end 3 and a distal end 4, an axis a extending between the proximal end 3 and the distal end, at least one drive member, a piston rod 6 adapted to be driven along the axis by the drive member, an indicator 5 adapted to provide positional information about a position of the piston rod 6 relative to the proximal end 3, wherein the indicator 5 and the piston rod 6 are configured to convert a movement of the piston rod 6 with respect to the housing 2 into a rotational movement of the indicator 5. The indicator 5 comprises a rotation member 7 configured to convert movement of the piston rod 6 into the rotational movement of the indicator 5 with the indicator 5 being coupleable to the piston rod 6 via the rotation member 7 and wherein at least a part of the rotation member 7 is arranged within the piston rod 6.
