The Mux (Multiplexer) Shield adds the capacity for up to 48 inputs or outputs on the Arduino and Arduino Mega.

Using three Texas Instruments CD74HC4067 Analog Multiplexers, the Mux Shield makes it possible to have 48 analog/digital inputs or digital outputs in many combinations.

The Mux Shield comes with 5V and Ground headers so you’ll have power available to each input or output and comes with stackable headers installed.

Arduino Mayhew Labs Mux Shield Pinouts