All I can say is that I'm very happy with the mask after diving with it. Vision was supper clear and the field of view was great. As for the seal... the large skirt made it almost impossible to create a leak by cracking the mask. I had to almost lift the whole side. My last mask... if I even looked left or right would leak. I think i could twist this new atomic around my bald head and once it arrived back at my eyes it would be still void of water. So in short, I'm very happy to spend $100 on a mask that FITS!!! The extras are nice.
If a mask came with a free dive computer I'd be unhappy if it didn't fit. (well maybe that would be ok
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