Beauty, Personal Care and Cosmetic Products Design Dr.Bei F3 Portable Water Flosser by DR.BEI F3, as a portable water flosser, is just the size of the iPhone when packed and convenient for storage. Due to the airtightness requirements in the industry, the relief port must be open when drawing the water tank, while F3's unique wedge-shaped design can naturally deflate and reduce negative pressure without opening the relief port, and will automatically clip-on after stretching in place and form a good seal. The overall design is simple. The dust-proof cover at the water inlet is brief and delicate, while the wavy glass shell with skid-resistant function gives users a new experience.