Festool Sys Vac Spares to consider

[MMCO]

I have the complete Sys Vac System and recently thought about obtaining spare parts to keep it operating for many years to come. I have bought the rubber seals for both bases and am curious what other spares I should consider, i.e. parts that will wear out. I am hoping there are folks on here that have more knowledge that can make suggestions. Thank you in advance.