Pressurized breather caps with double valve and vandal-proof device with cover and threaded fitting in technopolymer, NBR packing ring, technopolymer overpressure valve with O-ring in NBR, suction valve with technopolymer sealing disc with O-ring in NBR and stainless steel spring, annular air filter in reticulated polyurethane foam, filtration fineness 40 µ and dipstick in flat section phosphated steel.