This ad from 1991 is for Nestle's Milky Bar, the classic "It's the Milky Bar Kid" slogan.
The ad shown is actually the very first one to use this slogan from 1961 the only difference here is the 30th Anniversary title in colour shown at the end. I suspect the "Nestle's Milky Bar!" jingle has been changed as originally Nestle was pronounced incorrectly when shown in the UK.