Checking spare battery charge status

[cozzy]

I noticed today whilst cleaning the terminals of my spare battery that if you touch all 4 as per the picture then the battery flashes how many bars it's charged.
I did not know this.
Saves plugging it in to the charger or fitting it to the bike.

 

[Tubby G]

What happens if you put your tongue on them ?

 

[cozzy]

What happens if you put your tongue on them ?

Not falling for that again