It is provided a drug delivery device (1) comprising - a housing (4), - a number sleeve (7) contained within the housing (4) and being rotatable with respect thereto and - an axial retention mechanism (6) which is designed to axially restrain the number sleeve (7) to the housing (4) and to allow rotation of the number sleeve (7) with respect to the housing (4), wherein the axial retention mechanism (6) comprises a retention element (11).It is further provided a method of assembly of such a drug delivery device (1).本發明提供了一種藥物輸送裝置(1),該裝置包括:- 殼體(4),- 數字套筒(7),該數字套筒(7)容納在該殼體(4)內,並且能夠相對於該殼體(4)旋轉,和- 軸向保持機構(6),其設計成將該數字套筒(7)軸向約束到該殼體(4),並且允許該數字套筒(7)相對於該殼體(4)旋轉,其中,該軸向保持機構(6)包括保持元件(11)。本發明還提供了一種該藥物輸送裝置(1)的組裝方法。1‧‧‧藥物輸送裝置4‧‧‧殼體4.1‧‧‧螺紋4.2‧‧‧殼體保持元件4.2.1‧‧‧保持用徑向抵靠部4.3‧‧‧殼體約束元件4.3.1‧‧‧約束用徑向抵靠部7‧‧‧數字套筒7.1‧‧‧凹槽7.2‧‧‧傾斜表面7.3‧‧‧遠端11‧‧‧保持元件11.2‧‧‧鈎狀自由端A‧‧‧縱向軸線P‧‧‧近側方向D‧‧‧遠側方向
