The coating on those metal screens will eventually chip off, allowing it to rust.

Their claws don't hurt. But clawed frogs, for the most part, don't like being handled. I do have one female that will swim into my hand and await her worm. Even if she tried to scratch, she wouldn't hurt. All that would happen is she would be propelled in the opposite direction. Every other frog just swim away from my hand.

Never handle a clawed frog out of the water unless it is a rescue mission for an escaped frog.