This is a simple light force actuator that is used to provide adequate and even pressure on the surfaces of potentiometer sensors.
This is basically an instructional kit which includes a 2.9" special edition flex sensor, one 22K resistor, and a 3 page instruction sheet that has a simple exercise on how to sense a bend with a flex sensor and arduino.
This Sensor Kit teaches you how to use a linear touch pot with Arduino. Of course the contents of the kit can be used for many other activities.