Heather Rhoads of San Diego wholesaler Miami Wholesale Sunglasses sells numerous brands of wholesale sunglasses. She said Miami used to sell about 10 different styles of Locs, but has increased that over time to 30 different styles to meet a rising demand.

"In recent years, they've definitely been increasing in popularity," Rhoads said. "Locs is one of the top two brands that we offer."

Locs sunglasses feature a distinctive blocky style that has long been popular among rappers and movie stars. Rappers like Eazy-E, B.G. Knocc Out and Brotha Lynch Hung became synonymous with Locs glasses.

Historically, Locs always had an all-black, hard core gangster style look with thicker frames and the famous logo. But more recently the brand has been diversifying its style, offering all-white styles as well as styles with adornments such as skulls.

While Locs have long been a hot seller on the West Coast, the brand is now popular across the United States, Rhoads said, adding that the brand now has a wider appeal across consumer demographics. One reason for this growing popularity is that A-list rappers like Ice Cube, Ice-T and Snoop Dogg have been able to cross over into film and television while sporting their hard-core Locs shades.