Instruction: Output yes if the supporting document can answer the given question. Otherwise, output no.

Input:
Question: Do the +2 masks have an insert lens in the bottom?  I am looking for a single lens, not a bifocal, that has +2 magnification.   I was told that they all only have magnification on the bottom portion of the mask, which is not what I am looking for.  In other words, is the entire lens a single piece of glass with +2 magnification?
Document: I purchased this mask for snorkeling on a vacation. My vision is not good, and I wear 3+ reading glasses and need correction for distant vision about 1+. This mask was corrected 3+ on the bottom part, and I was concerned that I would not see well through the distant portion, but that was not so at all. It was as if I was wearing excellent bifocal glasses. The mask fit well and did not leak. I was able to forget my equipment and enjoy the view.
I got this mask so I could see my camera details underwater. The mask fits me perfectly and the bifocal portion, low in the vision area, is perfect for me. Highly recormmeded over the stick-on products I have tried
It is okay as a mask. However, I find the prescription lens portion too low and too small. It was not useful at all during my dive.
After checking some reading glasses at a drugstore, I figured that I needed about a +1.5X lens and this is what I ordered from Promate. Wow, what a difference these make compared to my normal mask! Instead of everything being a fuzz I can finally see so well, and yet this is without looking up my prescription numbers, (which are expired now anyway) or the extra expence of having custom lenses ground.
This trim piece was about 3/8" wide running from top of mask down entire nose. Not certain, but it looks very similar to the other mask mentioned.Regardless, the problem with the mask I received is there is such a small amount of the soft sealing silicone material along the top edge of the mask that when you put the mask on your face the hard plastic part of the mask was hitting the center of my forehead before the soft silicone ever had a chance to seal against my forehead.
The lenses added to the mask are placed too low to be useful, but since they have no magnifying power, their position insignificant. I think they are plain glass.
I lhoped these would give me better view of the fish. They did not. I bought instead a snorkeling mask with a 2 diopter rating and they are so wonderful. The difference in what I can see while snorkeling is amazing.
the local dive shop wanted $250. to order this mask. They are perfect. I highly recommend these. For 2 years I went snorkeling with bad vision, now I can see the fish before they get to me. Makes a difference.
The bifocal lenses it must be higher almost at the middle of the mask its to short to see well
I was looking for a reasonably priced prescription snorkel mask to take to the Caribbean for repeated use. This filled the bill perfectly! It fit well, sealed well, and made ALL THE DIFFERENCE IN THE WORLD in my ability to see underwater. I am very happy with this purchase!
Answer: no