SainSmart Sensor Shield V4.0 allows you to connect to various modules like sensors, servos, relays, buttons, potentiometers just plug and play! Each functional module has buckled port with VCC, GND and Output, which has corresponding port on the Sensor Shield, connected with a plain 2.54mm dual-female cable you may start playing already. Buckled brick cables are like cement for bricks, make the connections easier, secure and more professional looking. Technical Details : Operating Voltage: 5VDC. Input Voltage (recommended): 7-12VDC. Input Voltage (limits): 6-20VDC. Buckled Analog Port:Handy, solid connection to 6 Analog inputs with VCC/GND. Digital IO port:13 ports prepared to digital modules or servos. Analog IO Port:2.54 grid male pin header connections. Buckled Communication Port:Selectable between I2C and UART. Package Content : 1x SainSmart Sensor Shield V4.