Pressfitting systems for Compressed Air Installations, LABhttps://www.racmet.com/fr-ww/pressfitting-systems-for-compressed-air-installations.aspxThe parts are all in AISI 316L pressfitting stainless steel inoxPRES and galvanized pressfitting system steelPRES. ... In such cases it is recommended to use pipes in AISI 316L or AISI 304 stainless steel. ... The galvanized tube corrodes inside without the possibility of surveillance and intervention.