The present invention generally relates to an assembly for a drug delivery device comprising a first threaded member (50, 50 '), a second threaded member (40, 60') with a longitudinal geometrical axis and a thread (61). , which has at least two consecutive portions (62, 63, 64) with different advances. the first threaded member (50, 50 ') and the second threaded member (40, 60') are adapted and arranged to rotate with respect to each other about the longitudinal geometric axis of the second threaded member (40, 60 ') during a dose setting operation of the assembly, the first threaded member (50, 50 ') thereby being axially displaced along the second threaded member (40, 60') from a start position to an end position with respect to the second threaded member (40, 60 '), due to the mechanical cooperation of the first threaded member (50, 50') with the thread (61). According to the invention, a quick portion (62, 64) of the thread (61) having a feed greater than a slow portion (63) of the thread (61) comprises a multiple start thread and the slow portion (63). ) comprises fewer beginnings than the quick portion (62, 64). The invention is further directed to a medicament delivery device for regulating and administering various user variable doses of a medicament comprising such a kit.a presente invenção refere-se geralmente a um conjunto para um dispositivo de administração de medicamento compreendendo um primeiro membro roscado (50, 50'), um segundo membro roscado (40, 60') com um eixo geométrico longitudinal e uma rosca (61), que tem pelo menos duas porções consecutivas (62, 63, 64) com avanços diferentes. o primeiro membro roscado (50, 50') e o segundo membro roscado (40, 60') são adaptados e dispostos para rodarem um com respeito ao outro em torno do eixo geométrico longitudinal do segundo membro roscado (40, 60'), durante uma operação de regulagem de dose do conjunto, o primeiro membro roscado (50, 50') desse modo sendo axialmente deslocado ao longo do segundo memb
