Side air bags in protection group?

Asked Dodge to send me a Charger brochure. It describes side-curtain air bags as available in the protection group package. In an additional insert they sent along there's a line item for Front & Rear Side Window Curtain Air bag AND another line item for Supplemental Side Air Bags**. Of course there's no explanation of what the ** means on that page.

Does the car only have side-curtain air bags? Thanks