SparkFun Rotary Switch Potentiometer Breakout Boards, Sparkfun Originals Capacitive if you look at the

if you look at the device from the bottom the pin out goes

It essentially combines a simple optical heart rate sensor with amplification and noise cancellation circuitry making it fast and easy to get reliable pulse readings

and Cat6 Ethernet cables

This board is buffered and power protected so that you can do some really evil things to the programmer without killing it

SparkFun Rotary Switch Potentiometer Breakout Boards, Sparkfun Originals Capacitive if you look at theThe SparkFun Rotary Switch Potentiometer Breakout is a small board the allows you to add resistors to a 10 position rotary switch, turning it into a potentiometer with 10 discrete steps. Multiple applications require potentiometers that are hard to find due to specific resistance values or custom tapers, the Rotary Switch Potentiometer board allows you to populate your own resistors to help match situations where ordinary parts aren? t available or