A carton for a medical device includes a cover and an inner sidewall coupled to the cover. The inner sidewall includes a locking tab receiving slot. The carton further includes a first outer sidewall assembly comprising a self-locking tab configured to be inserted into the locking tab receiving slot, the self-locking tab having a first width greater than a second width of the locking tab receiving slot. The self-locking tab utilizes the geometry of the carton to create the seal. The self-locking tab is cut in a specific shape such that when it is inserted into the locking tab receiving slot, the self-locking tab locks the carton closed. Further, a perforated cut around the locking tab receiving slot allows a locking tab release flap of the carton to be lifted, freeing the self-locking tab so the carton may be opened.