ATRDB12 is an adjustable resistor decade box used to manually set resistance values for circuit testing, prototyping, troubleshooting, and laboratory work. It provides a resistance range from 0.1 ohm to 100 Mohm in a compact bench tool.

With 0.1 ohm adjustment resolution and 1% accuracy, ATRDB12 helps users quickly substitute resistor values without repeatedly swapping discrete resistors. It is useful for circuit evaluation, design verification, repair, and education.

The front panel is easy to read during adjustment, and the metal enclosure is durable for regular bench use. ATRDB12 is a practical tool when fast, repeatable resistance selection is needed.