"We don't stop playing because we grow old; we grow old because we stop playing." ~George Bernard Shaw
"Look at everything as though you were seeing it either for the first or last time." ~Betty Smith, A Tree Grows in Brooklyn
And for heavens sake have a great day! Here's the answer: It's called a cassette and it is for a bicycle. It will be put on my sweetie's bicycle with a brand new bike chain. This cassette will give the bike better gearing and make climbing hills a lot easier!