@foxymammaThe prism might be something different though. Is that for double vision?
@MarT: yes, In eyeglasses, 
risms are used primarily for double vision, positional correction, or convergence correction. its measurements are in the script so I am not too worried about the prism part mostly the progressive part. I ususally buy at Target and they have had to redo mine a couple times so that is my concern.
I will have to check the return or exchange policy. But it is a cheap gamble in comparison. I will probably try it with a cheap pair just to see or with some sunglasses. 4951