Features: brand new and high quality Before using the adjustable constant voltage and constant current power supply, you need to set the constant current for protection value first, then set the output voltage, and then start working. The adjustable power supply motherboard DIY kit is suitable for accessories with idle for transformers in hand or refitting old power supplies, using its chassis, for transformers, meter heads and other accessories. This kit provides all components and circuit schematic diagrams, but for transformers, housings, and voltage and current meters are not included. This power supply is the previous linear adjustable design idea, the output for protection circuit is not perfect, and it is limited to amateur learning and experimental applications. Please don'for t use it to power valuable electronic equipment! This product is provided as a kit and needs to be assembled by itself, including electronic component welding, circuit debugging, etc., which are complex actions that require experience. Specifications: Material: Plastic & Electronics Size: Approx. 10x10CM/3.93x3.93inch Package Includes: 1x Power Board Kit（for Transformers, Housings, Voltage and Current Meters Are Not Included） note: 1.Please allow 1-2cm errors due to manual measurement, make sure that you do not mind before you order. 2.Due to the difference between different monitors, the picture may not reflect the actual color of the item. 3.Electronic products are closely related to electricity. Please confirm your purchase according to your own electronic production capabilities.