From the Super Mario Wiki, the Mario encyclopedia
Interrupting Frame is an offensive item found in Mario Kart Arcade GP 2 and Mario Kart Arcade GP DX. It homes onto the opponent once locked on. After the opponent gets hit by the item, multiple, moving frames of the character that has thrown it obscure the opponent's view, similar to the Blooper in other Mario Kart games. Like most other items in the game, it eventually fades away.