Proj 365 June 28th

OK, mystery challenge time. The bottle at the right is a Nehi soda bottle. (presumably grape). BUT the top says Tab. What is inside the bottle without opening it?

BTW I know only because I worked on the bottling assembly line downstairs where we pulled bottles from the cardboard cartons and replaced cartons as needed. Most likely the reason I have a hearing loss. (Back then nobody wore hearing protection as nobody really knew or cared.) We  estimated we heard over 100,000 bottles going "Clink" at any instant on 7 different lines. You had to yell / scream "Whhooo" like an owl at somebody 5 feet away to get there attention. Beyond 5' it was useless.