I was going to buy some cheap sunglasses from HK. I did.
Then I went to a glass shop to get my new actual degree glasses and the sales was introducing me to the sunglasses. i told him i just bought some from the outside stands and he said he can check if those ones are actually real - like if they can actually block UV rays and some other harmful sun light. he had this machine to check it and it showed that it blocked none. =( however, the one that he was introducing me from his shop, was able to blocked all and therefore, a "0" showed on the machine.

The sales told me that it is better to not wear those "fake" sunglasses out in the sun than to wear them because they will harm your eyes. Without sunglasses, you will squint and your pupils (?) will become smaller. but with sunglasses, even those fake ones, your pupils won't become small but themselves and instead it will be wide open with harmful uv rays hurting them right in.

I'm not sure, but thats what I understood when he was explaining.