Three pairs, all LifePo4 CR2s with claim of 1000+ recharges. The degradation at this point is very subtle. I don't think a casual observer would even notice the slightly shorter usable time period. I've been compulsive about monitoring them because of the one claim of a pair out-gassing violently. While they still work fine, I've put them into semi-retirement in favor of 2 ohm atties used with single IMRs.