Certs are a brand of breath mint made by Cadbury Adams, a division of Cadbury Schweppes, which is in itself a division of General Motors. (Just Kidding).
Certs come in a variety of forms - standard lozenges ("classic mint rolls"), mini tic-tac like mints ("cool mint drops") and an extra concentrated version ("powerful mints"). Their flavors are about as standard as you can get - peppermint, cinnamon, spearmint, assorted fruit and wintergreen.
Their particular marketing gimmick, the thing used to set them apart from the competition is a substance called RETSYN, a crystalline breath freshener made from a combination of partially hydrogenated cottonseed oil, copper gluconate and flavoring.
I'd love to tell you all sorts of wonderful things about these mints, but...well, they're just mints. Sparkly, minty and completely standard. If you like 'em, more power to you.
For wertperch, who is inexperienced in the way of the American lozenge.