Gikfun DIY SMD SMT Welding Practice Soldering Skill Training Board Ek7028 After welding, just connect electricity (3-12V) to see the effect. You can quickly judge the welding effect. The welding product is a beautiful water lamp circuit. The back of the board with mm/Inch ruler, Easy to measure component It's DIY Kits, Blue Led English manual down from links: http://pan.baidu.com/s/1jGCOAxC With English manual in the package The welding product is a beautiful water lamp circuit. This is a great little training kit for those who want to get a feel for SMD soldering. It contains a PCB with 2 sides, English instructions and all the components needed. The PCB board has clearly marked the electronics components, it&#039;s easy to assemble. The solder learning kit has proper circuit design with led indicator, easy to check your soldering result, them will be a flashing LED light after soldered and powered with 3-12V, very interesting effect. The back of the PCB board is marked with mm/in scale for easy measurement of components, and also marked with PCB line width example, can be used as a design PCB reference. PCB Size: 85.6mm(L)x 54mm (W) x1.6mm (H) Operating Voltage: 3-12V This is blue Led, we also have red Led version, ASIN is   B00Y20JYTM The product is used for learning. Suitable for people who want to improve the welding skills. Comes with English user manual and online file, which will guide you how to finish step by step. If you need technology supports, or meet other problem, please send e-mail to us, we will help you as soon as possible.