ALLOSUN Digital Battery Tester BT21 Power supplied by 2 pieces 1.5V LR44 battery.(Battery not provided by seller) The battery tester allows you to check the charge of 1.5 volt and 9 volt quickly and easily. Mini size , quite easy to carry. It can be used for AAA,AA,C,D,6F22 batteries and so on. It is practical and easy to operate. Test arm ( for battery terminal) Display Power Switch Range Switch Voltage range : 1.2 - 9V Accuracy : +/- (1.5% + 3) Test current : 20 -120mA Load resistance : 75 ohm 2W Max input protection : 12V Dimension: 89x46x20mm Weight : 47g ( including batteries)