When they pull the last of all the copper KSUs and replace them with fiber optic VoIP...it would not surprise me if the cut-order phone call was made over a 1A2 6-button set. <snicker>
In all seriousness, they were built like a rock. Pulled one years ago that had been in service at least thirty years with non-solid state 400E line cards - just current sensing relays.
