I just tested the glasses in the sea, free diving, as a test I put the oculo without worrying about the positioning on the face, I did it about 5 times, and did not enter water, as far as the subject is sealing glasses is efficient, I recommend, the sharpness and field of view are also great, The snorquel is very good, but its protection system I found too much, it closes the air intake very easy, cutting the air intake frequently... But it's good... It is a matter of getting used to and avoiding agitated waters... Overall... I am happy with the purchase, I recommend it to anyone who wants a good glasses... I'm a 1,80cm man, and the glasses are very comfortable...