7-digit digital display 2 AAA batteries power supply (without battery, you need to prepare yourself) Automatic shutdown in 30 seconds without action Addition, subtraction, multiplication and division operations Conversion, open the root sign 4-ring, 5-ring resistance conversion Arithmetic function Non-finished products, is diy welding kit, need some welding skills, can provide product instructions DIY Electronic Kits LED Digital Tube Calculators 51 Microcontroller Control Resistance Conversion DIY Soldering Projects It's DIY kits, needs to finish by yourself. Colour:A:Blue/B:Green/C:Red Material:Plastic Package Contents: 1 * DIY Calculator Electronics Kit Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.