A pressurized fluid cartridge comprising: i) a bottom, a lateral wall and an upper wall opposite the bottom; ii) a safety means that opposes the leak of fluid from the cartridge after perforation of a predetermined perforable part afforded in the upper wall; said safety means comprising: *) a fluid dynamic seal means which in a fluid dynamic seal configuration contacts the upper wall along an imaginary closed line which surrounds said predetermined perforable part; *) a flexible strip which pushes said seal means towards the upper wall, the strip being a single body to which the fluid dynamic seal means is assembled; said strip comprising: - a housing cup; - at least a first and a second arm (51, 52); - an intermediate zone to the first and the second arm (51, 52) in which said cup is afforded and from which the first and the second arm (51, 52) extend towards the lateral wall, said cup being made of the same material and in a single body with the first and the second arm (51, 52); characterised in that the fluid dynamic seal means is at least partially housed in the housing cup; the housing cup defining a concavity facing the upper wall. i) a bottom, a lateral wall and an upper wall opposite the bottom; ii) a safety means that opposes the leak of fluid from the cartridge after perforation of a predetermined perforable part afforded in the upper wall; said safety means comprising: *) a fluid dynamic seal means which in a fluid dynamic seal configuration contacts the upper wall along an imaginary closed line which surrounds said predetermined perforable part; *) a flexible strip which pushes said seal means towards the upper wall, the strip being a single body to which the fluid dynamic seal means is assembled; said strip comprising: - a housing cup; - at least a first and a second arm (51, 52); - an intermediate zone to the first and the second arm (51, 52) in which said cup is afforded and from which the first and the second arm (51, 52) extend towards the lateral wall, said cup being made of the same material and in a single body with the first and the second arm (51, 52); *) a fluid dynamic seal means which in a fluid dynamic seal configuration contacts the upper wall along an imaginary closed line which surrounds said predetermined perforable part; *) a flexible strip which pushes said seal means towards the upper wall, the strip being a single body to which the fluid dynamic seal means is assembled; said strip comprising: - a housing cup; - at least a first and a second arm (51, 52); - an intermediate zone to the first and the second arm (51, 52) in which said cup is afforded and from which the first and the second arm (51, 52) extend towards the lateral wall, said cup being made of the same material and in a single body with the first and the second arm (51, 52); - a housing cup; - at least a first and a second arm (51, 52); - an intermediate zone to the first and the second arm (51, 52) in which said cup is afforded and from which the first and the second arm (51, 52) extend towards the lateral wall, said cup being made of the same material and in a single body with the first and the second arm (51, 52); characterised in that the fluid dynamic seal means is at least partially housed in the housing cup; the housing cup defining a concavity facing the upper wall.