Monel K500 Spacer Flanges has useful resistance to boiling sulfuric acid up to 40 % concentration, to 60 % concentration at 176 Degree F and in all concentrations to 150 Degree F. Stronger than 400, alloy K500 even retains this strength in corrosive conditions, resisting both pure and salt water, as well as non-oxidizing mineral acids, salts, alkalis, and sour gas. Изключение е, че Monel K500 закопчалки могат да бъдат по-предразположени към напукване на корозия на стрес в някои среди, отколкото Monel 400.