__ Ring; Round Swimming Aid Worn by Children
Puzzle 17 of Brad Pitt Easy Pack
Question is: __ Ring; Round Swimming Aid Worn by Children
and the answer is: RUBBER
Word Meaning:
RUBBER — (uncountable, countable) Pliable material derived from the sap of the rubber tree; a hydrocarbon biopolymer of isoprene.
Definitions from Wiktionary.