The Hyper Tough TD35237J pocket size battery tester is easy to use, and very convenient. Great to use to check D, C, AA, AAA, 9V, 1.5V and button cell. Meter display to check if batteries are good, low power, or in need of replacement. Analog scale quickly identifies battery charge level. Moveable contact arm fits multiple battery sizes. Measures a battery under load and indicates the condition. This Hyper Tough battery tester is small and practical, compact size and lightweight, easy to carry. Perfect for home use, easy to read, the analog display needle moves on a color-coded calibrated scale to indicate the status of the battery. This will keep you from wasting good batteries by throwing out good ones. It is activated by the battery being checked. A must by for anyone who uses regular or rechargeable batteries on a regular basis. Pocket Size Great to use to check D, C, AA, AAA, 9V, 1.5V and button cell Perfect for home use Analog display needle moves on a color-coded calibrated scale to indicate the status of the battery