Octopus Electronic Bricks, you can use them to build electronics projects just as easy as piling bricks. By using Octopus electronic bricks, you may connect Arduino/Freaduino compatible boards easily with various digital, analog and I2C/Uart interfaces. These the breadboard-less firm connection are prepared to extensive modules like poteniometers, sensors, relays, servos...even buttons, just plug and play.
Photo Interrupter Sensor is a sensor module based on ITR9608 photoelectric switch, together with special Arduino shield in use.It has been widely used in parts counting, motor speed and so on. Three pins electronic building blocks interface, input 5V - GND, S for digital signal output.