Programmable 4-20mA Current Signal Generator with LCD Digital Display Back Light E-983 Display Modes: 4-20ma Current Value, 0-100 (%) Percentage, 0.0-50.0 (Hz) Output Current Signal: Default 4–20ma, Max. 3ma To 21ma Power Supply Voltage:15V To 30V Sampling Resistor:10Ω—500Ω Display Precision:0.01ma Max. Output Precision:±0.5% VOLTAGE-24 V  

The Mega2560 Shield makes it easy for you to design custom circuits. You can solder parts to the prototyping area to create your project, or use it with a small solderless breadboard to quickly test circuit ideas without having to solder. It's got extra connections for all of the Arduino I/O pins, and it's got space to mount through-hole and surface mount integrated circuits. It's a convenient way to make your custom circuit and Arduino into a single module.