Electronic Hourglass led DIY Kits Welding Practice Board red Blue Green (Green)

This is a beautiful electronic hourglass that is fun to build and nice to look at when finished, it is not only a PCB board for practicing welding skills, but also a decorative gift for you. The suite adopts double layer PCB, and the circuit consists of 30 pieces white LED blue ray, has clearly marked the electronics components, very easy to assemble. Under the control of MCU program, it displays analog hourglass image. It can be used as decoration of small night light. Warm tips: Power Supply Voltage: 3.3-5V Before soldering the LEDs, it is recommended to use a multimeter to check if there are any LEDs that are not bright. Please make sure all components in right direction and right place; and check whether pseudo and float welding, this is very important in practicing and testing.