I recently bought my first pair of Oakleys. Flak jacket xlj mph grey smoke frame with ice iridium lenses. My question is this there are no sku or size markings on the ear stems. Is that normal for a mph? I bought them from 6 pm llc. They feel like the real thing, I do own a pair of fakes and the difference is very noticeable. Should I be worried?? Is 6 pm a reputable site?