What does a rollie polie look like?

Rollie pollies are black or gray and they have lines on there back.

I hope you find a rollie pollie! :-)

Whoever answered this question originally: it's theirback, genius, not there back. Don't you know the difference between their (possessive pronoun) and there (noun, adverb, or interjection, depending on how "there" is used in a sentence or phrase)?