This is Clear Plastic Case for Arduino UNO R3. The case is a two-piece injection-molded enclosure that holds together around the Arduino and it holds the Arduino firmly in place. As it is transparent is perfect for letting you see your Arduino Uno and make any needed adjustments easily. The transparent Case for the UNO R3 board is of high-grade acrylic, which provides excellent protection. This is unique design provides an easy connection to other components. The dimension of the enclosure box is the same as the original Arduino Uno R3.