AT Tech Lab on Instagram: "A 10-second clip shows a door lock with no visible keyhole. Instead of inserting a key, the person places a special orange handle over the lock and twists it. A hidden cover slides away, revealing the real keyhole beneath. The key goes in, the door unlocks smoothly. A smart example of advanced home security and clever mechanical design. Follow me for more @ATTechLab #homesecurity #clevergadgets #mechanicalengineering #viralreels #trending #reelsinstagram"