Abstract: Fuze including safety element (30) includes an acceleration detector (31) that acts on a timer (32) coacting with a primer housing rotor (14). Rotation of the rotor can be halted by a second safety device (35) responsive to the dynamic pressure generated by the speed of the projectile (11) in flight. For this purpose, the device includes a diaphragm (36) engaging a flexible blade (51) to space apart the end (55) of the blade and the rotor when the dynamic pressure has a predetermined value, whereby a primer (18) can be moved into line in the explosive train. When the dynamic pressure is too low, the end (55) stops the rotor (14) from rotating and the firing procedure is also blocked in a notch in the rotor (14). The resulting fuze thus has highly reliable dual safety element responsive to two separate physical phenomena and having a simple construction.