Digital Tube Display Calculator Kit - Power options: Supports Type-C power interface DC5V or button battery power supply. The battery installation port has a side hole for easy battery removal. - Core functions: Not only performs arithmetic operations (addition, subtraction, multiplication, division) but also converts color-band resistor values. A versatile tool for electronics practice and learning. - Construction and durability: Built from dedicated circuit boards, digital display tubes, a microcontroller, buttons and other components, providing stable performance and long service life. - Applications and suitability: Production kit for the digital tube display calculator; ideal for welding exercises, electronic training, experiments and DIY projects. Suitable for electronics enthusiasts to practice assembly and handling. - Practical use scenarios: 1) Use as a hands-on soldering/welding exercise by assembling and testing the calculator. 2) In electronics classes to perform calculations and convert resistor values during lessons. 3) Incorporate into DIY projects that require a built-in calculator and resistor value conversion tool.