SainSmart 20 Sensor Modules Education Starter Kit with 1 Relay Module + HC-SR04 Distance Sensor for Arduino UNO MEGA2560 R3 Duemilanove Robot The kit has more than 16 projects for the beginners. This is the new SainSmart Module Starter Kit, developed specially for those beginners who are interested in Arduino. A complete set of Arduino's most common and useful electronic components. What's more. Detailed PDF tutorial including project introduction and their source code will be provided after purchase.