"Tough chewers" refers to animals, usually pets like dogs, who have a strong tendency to chew on things very aggressively or persistently. Full definition
Kartoffel loves any and all toys, particularly tennis balls and toys he can really chew on (some of his favorites are listed in our durable dog toys for tough chewers post). (woofwhiskers.com)
The toys are designed to satisfy tough chewers that go through other toys in minutes. (thepetaisle.com)
my girls are not tough chewers, they are small dogs, so i would give this to a friend or donate to a rescue group. (mydoglikes.com)