The present disclosure provides a compressible fluid device (1), such as a gas spring. The device comprises a casing (11) defining a compression chamber (12), a piston (15), which is movable in the chamber (12), and a safety member (2) placed in such a manner as to be struck by the piston (15) in the event of the piston overstriking, whereby at least some of the compressible fluid is evacuated from the compression chamber (12). The device further comprises a pre-strike member (25), that is arranged to be struck before the safety member (2) is struck, such that the safety member (2) is only struck once a predetermined overstroke force has been achieved.