A Pocket Monster Pokemon ball that converts to a yo-yo. Made by Bandai. Uses a transaxle system and starburst response. Included is a reverse twist 3-strand cotton string which is uncommon. To play the yo-yo you needed to remove the black plastic insert from the middle circumference. When you were done yo-yoing, you slid the plastic insert back into place to complete the ball shape. A total of five Pokemon ball yo-yos were available.
More of a novelty yo-yo with limited functional playability. It's unknown how these were originally sold, although the packaging suggests that it may have been either dispensed from a vending machine or from a counter-top display box.
The Pokemon ball in this exhibit is known as the Master Ball. It is supposed to be a rare Poke ball that never fails in an attempt to catch a Pokemon. Pokemon balls are used in the children's Pokemon fantasy game to figuratively capture and store pocket monsters.