Features: DIY kit: Provides a simple metal detector DIY kit,. Metal detection function: It can detect surrounding metal objects, help to learn electronic circuit principles. Loose circuit board: The product provides loose circuit boards that require users to solder and assemble. Usage: Used for gaming entertainment, security checks, and searching for metal objects. Detection: 3-5.0cm, the larger the metal area, the farther the detection distance, conversely. Specifications: Material: Metal+PCB PCB Size: about 185x60mm/7.28x2.36inch Name: Metal Detector Manufacturing Kit Working current: around 23mA (under normal alarm conditions) Static working current: 3.7mA (without alarm) Power Supply: Two CR2032 button batteries (not included) Working power supply: 3-5V Package Includes: 1Pc Metal Detector Electronics DIY Kit note: Loose parts, you need to weld and assemble them yourself. Please allow 1-2cm errors due to manual measurement. Please allow for slight color differences due to different display resolution.