●🏊【Portable】:The diving bottle header is portable and easy to operate. ●🏊【LUMINOUS FUNCTION】:The pressure gauge has a luminous function, and it is still very clear under 80m. ●🏊【PROFESSIONAL MANUFACTURING】:With high accuracy and reliability, our diving valve is conform to strict quality and control standard, dependable to use. ●🏊【RECOMMENDATION】:It is recommended to match using 0.5L diving bottle. Breathing underwater for up to 5~10 minutes (Duration varies according to individual vital capacity). ●🏊【GUARANTEE】:If you are not satisfied with our product, you can send emails to us at any time. We will reply you within 24 hours and help you solve your problem.