You should have a set of stencil letters and mark every battery you rebuild or repair.
Often, too, they were coloured by stencil plates or freely by hand.
When it is to be used with a stencil it must be made thicker than when it is used with a brush.
Then the stencil had to be taken from the roller that the latter might be inked again.
Only the parts unprotected by the stencil ...