SparkFun Decade Resistance Box
This is the SparkFun Decade Resistance Box, an involved PTH soldering kit that allows you to quickly and accurately dial in a specific resistance value between 0 and 999,990 Ω, in 10 Ω increments. The concept is simple, a decade box is a tool that contains resistors of many values that can be accessed via mechanical switches. All you need to do is just adjust the knobs to output any of the discrete resistances offered by the box. Once assembled, each kit will have controls that correspond to the digits in a decimal number - a control for the tens position, a control for the hundreds position, and so on.