Faria 2" Ammeter Black w/Stainless Steel Bezel (20-0-20 Amps)2" Ammeter Black with Stainless Steel Bezel (20 0 20 Amps) An ammeter indicates the current flow through the battery charging system. A "zero center" ammeter, during chargine, shows a (+) positive reading indicating the current is flowing to the battery (charge). A ( ) negative reading indicates current flowing away from the battery (discharge). Features: 2" Hole Size Black Stainless Steel Bezel 20 0 20 Amps A 2 inch black ammeter (20 0 20 ampere)