The present disclosure concerns an assembly for a drug delivery device (1) comprising a housing (3), a first abutment surface (64), a second abutment surface (21), and a detachable member (7) which is detachable from the housing (3) and attachable to the housing (3), wherein the assembly is configured such that, during detachment of the detachable member (7) from the housing (3) for an Nth time, N being a predetermined number, the first abutment surface (64) is brought into abutment with the second abutment surface (21), wherein the assembly is configured such that, when the first abutment surface (64) abuts with the second abutment surface (21), the detachable member (7) is enabled to be reattached to the housing (3) and, afterwards, the detachable member (7) is prevented from being detached from the housing (3).本發明有關用於藥物輸送裝置(1)之組件,包含外殼(3);第一鄰接表面(64);第二鄰接表面(21);及可分開構件(7),其係可由該外殼(3)分開,並可附接至該外殼(3);其中該組件被建構,使得於該可分開構件(7)之由該外殼(3)分開達第N次期間,N係一預定數目,該第一鄰接表面(64)被帶入與該第二鄰接表面(21)鄰接;其中該組件被建構,使得當該第一鄰接表面(64)與該第二鄰接表面(21)鄰接時,該可分開構件(7)係能夠被重新附接至該外殼(3),且後來,防止該可分開構件(7)由該外殼(3)分開。5‧‧‧計數構件19‧‧‧計數器驅動構件21‧‧‧第二鄰接表面64‧‧‧第一鄰接表面
