| abstract |
There is provided a cassette unit suitable for use with an auto-injector. The cassette unit comprises a cassette unit housing and a removable cap that in a capping position fits over and thereby, acts to close off, a needle projection aperture of the housing. The cassette unit housing has one or more first engagement features arranged for reversibly engaging one or more second engagement features of the removable cap for reversible lock engagement of the removable cap to the housing; and a shuttle lock control defining one or more blocking elements for selectively blocking movement of said first engagement features relative to said second engagement features. The shuttle lock control is axially movable relative to the cassette unit housing between a first 'cassette unused' position; a second 'cassette unlocked' position; and after replacement of the removable cap, a third 'cassette used' position, locating intermediate the first and second positions. |