Features: Perfect for electronics enthusiasts and hobbyists who enjoy building and assembling their own gadgets. These kits provide a fun and rewarding experience for both beginners and advanced users. Whether in your living room, office, or workshop, this DIY clock will be an addition to any space. Showcase your creativity and display your love for retro technology. AT89C2051 Digital Clock Kit: The control chip uses AT89C2051, and the digital tube uses three two-digit red common anode LED digital tubes, featuring a clear display and high brightness. Due to the scanning display mode, the display brightness can be adjusted by changing the resistance value of R4R10. The S1 button is used to calibrate the time; press and hold for over 2 seconds to enter the time calibration state and exit. Quick presses are used to adjust time values. A 3V backup battery is included in this circuit. During a power outage, the AT89C2051 uses the backup battery for power, and the clocks will not stop, although the digital tube will not display. It will serve as backup power after the main power is restored. Specifications: Material: Electronic Component Size: As the picture shows Item Number: AT89C2051 Working Voltage: DC5V-12V Note: Please allow 1-2 cm error due to manual measurement; ensure you don't mind before ordering. Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you for your understanding. Package Includes: 1 set LED Electronic Clock