The present disclosure relates to a supplementary device (1) configured to be mounted to a medicament delivery device (1), wherein the supplementary device comprises a casing (3), a button (5) configured to be received by the casing (3) and configured to actuate a trigger (6) of a medicament delivery device (2), wherein the button (5) is configured to be displaceable from an initial retracted position to an extended position relative to the casing (3), and a button locking member (7) configured to lock the button (5) in the retracted position of the button (5) to prevent displacement of the button (5) from the retracted position to the extended position, wherein the button locking member (7) is configured to release button (5) when the supplementary device (1) is mounted to a medicament delivery device (2), thereby enabling displacement of the button (5) from the retracted position to the extended position.本揭示內容有關補充裝置(1),被建構用於安裝至藥物輸送裝置(2),其中該補充裝置包含:殼套(3);按鈕(5),被建構用於藉由該殼套(3)所承接,且被建構用於致動藥物輸送裝置(2)之觸發器(6),其中該按鈕(5)被建構用於可由最初的縮回位置相對該殼套(3)位移至伸出位置;及按鈕鎖定構件(7),被建構用於將該按鈕(5)鎖定在該按鈕(5)之縮回位置中,以防止該按鈕(5)由該縮回位置位移至該伸出位置;其中該按鈕鎖定構件(7)被建構用於當該補充裝置(1)被安裝至藥物輸送裝置(2)時釋放按鈕(5),藉此能夠使該按鈕(5)由該縮回位置位移至該伸出位置。1‧‧‧補充裝置2‧‧‧藥物輸送裝置3‧‧‧殼套4a‧‧‧遠側端部份5‧‧‧按鈕5b‧‧‧凸緣6‧‧‧啟動按鈕7b‧‧‧支臂7c‧‧‧閂扣9‧‧‧推動件蓋子
