Hello all , I've got a p3 and 2 batteries . I recently bought a parallel charger board and there is a button and a screen display that I have no idea about . I thought it important to ask what the button does and what the little display is telling me. , I don't want to wreck my batteries there so expensive I've added a pic Also I bought it off eBay it was £10 . Is that dodgy ? Can anyone help me ? Thanks .