This is a vintage Alka Seltzer advertising barbecue apron. I think it's from the 70s-80s era. Featuring blue images of bubbling Alka Seltzer lozenges and their name text logo above red flames on center front pocket beneath the words ‘to the rescue’. I vaguely remember this ad but can only hear ‘plop plop fizz fizz’ lol!  
 
Pre-owned, very used! Sold AS IS because of stains. On the next sunny day I’m soaking this apron again and hanging it out to dry to see if the stains disappear.
 
The apron measures-
Center front length- 26 1/2”   
Waist- 25” across between the waist ties
Each tie is 34” long