PowerPuff Girls Mailable Puzzles. It's a Note and a Puzzle! Orange and green. 5 Puzzle Notes. 5 envelopes. 1 BIC Whirls Pen. Fun notes for parties, letters, sleepovers, thank you's, birthday invitations, pen pals! Use the pen to write your friends a note. Break the pieces apart, place in the envelope, and pop them in the mail (postage required)! Your friends will have fun piecing together your special letter! One unique puzzle piece may be saved to use as a decoration or bookmark. What's The Buzz? Cartoon Network, WB, Hasbro, 2000. Age 7+. New.