A team of Chinese students has developed DiveGuard, a new and affordable underwater communication system. The device utilizes acoustic signals to enable divers to exchange short text messages, improving both safety and coordination during underwater activities. DiveGuard addresses a critical need for reliable communication in environments where radio waves and other conventional methods fail. Recognizing its potential, DiveGuard was selected as a finalist in the 2026 Conrad Challenge, a prestigious competition recognizing innovative solutions. The system provides a cost-effective alternative to existing underwater communication technologies. This breakthrough promises to enhance underwater exploration, research, and professional diving operations. Its simplicity and affordability make it particularly valuable for a wide range of users.