Interestingly, you can keep the small batteries in the shifters and if the wires ever fail for some
reason the shifters will automatically switch to wireless.
That's neat. I've had my shifting go wonky (intermittent shifts) on a TransAm as one of the connectors ended up full of swamp juice (sweat, tears, snot?). Once it was popped and cleaned it was fine.
Interestingly, you can keep the small batteries in the shifters and if the wires ever fail for some
reason the shifters will automatically switch to wireless.