Capacitance Decade Box
The Extech 380405 Capacitance Decade Box is very popular for product design testing and calibration because it can be substituted into a circuit and function in the place of any component with a standard value easily. Alternatively, it can be used to identify the best value for circuit operation, then read that value from the switches. A capacitor of the size indicated by the decade box switches can then be put into the circuit.