Capacitance decade box for circuit design and prototyping, letting users dial in a target capacitance from 100pF up to 11.111uF across 5 decade ranges via front-panel slide switches in 100pF steps. Three binding posts allow isolated capacitor substitutions so a verified value can be tested in-circuit before a fixed part is soldered in. Rated to 5% substitution accuracy, compact and under a pound in weight.