Hey guys... i've never bought ray bans before... how do i know what size i want? what are the different mm's?

Not sure what some of these people are talking about. You can look above and see the that three sizes are 47mm (small), 50mm (med), and 54mm (large). If you don't know what size fits your face, you are better off finding a local Ray-Ban (brick and mortar) retailer and trying them on. Otherwise, if you have what you think is an average sized face, go with the 50mm and, if need be, exchange them for a larger or smaller set. Personally, I wear the 50mm size.

is the rayban black rb2140 54mm made in china or made in italy?

It’s a tricky affair. Original Ray-Ban Frames are “Designed “ in Italy, just like with Apple products… now, once that is said, I do believe they have ‘Assembly’ sites In various locations, including China. It’s all a ‘cheaper’ labor thing. Certain models (mostly the Iconic ones like Wayfarer and Clubmaster) are exclusively made in Italy (from what I have heard) while as other models, thou still designed in Italy may be assembled elsewhere.

Which ones are polarized? The gloss tortoise pictures the polarized glasses and are priced higher, but the description says they are not polarized.

Dear William, the product shown here is the 902/57 color which has polarized lenses. The item description is then incorrect. But if you buy it (from us for eg.) you will get 902/57 model with polarized lenses.Hope this helps.Sylvestre, otpikdirect_usa

What is the warranty on these? We purchased them in October and they’re very loose and the arm wiggles and doesn’t tighten appropriately.

If they are ORIGINAL Ray Ban, then Ray Ban offers and services any and all customer service related matters, and that is kind of irrelevant as to WHERE the purchase was made. You can contact Ray Ban Customer Service. I do believe you’re required to have ‘Proof of Purchase’. Or you can take it in to any of the Ray Ban Retailers (Lens Crafters or Sunglass huts, both owned by Ray Ban’s Parent Company).