3 ms·I got an electric one so I never need to remember to replace mine!by mfkp 8mo agoI got an electric one so I never need to remember to replace mine!efreak 7mo agoI think the electric ones need to be replaced eventually too, not not nearly as often.mfkp 7mo agoYeah I think it's something like a 20+ year lifespan, I doubt I'll even be living in the same house in 20 years.