| 摘要 |
The snorkel (1) is elliptical in cross section and has an internal wall (2) which divides it into two tubes (3, 4). One tube (3) is for inhaling and the other (4) is for exhaling. The top of the tubes are covered by a cover (5), made of the same material, which keeps out water but allows the passage of air. The lower end of the snorkel (8) is made in supple material and has two holes (9), in the form of projections, which are closed by two tongues (10, 11). A double valve (13) allows the alternate circulation of exhaled or inhaled air. |
