18/25 DOOR NUMBER. ON CARD AUTOGRAPH. The product is an 18/25 door number Panini 2018 Prime Racing Prime Number card featuring an autograph from Kyle Busch of Joe Gibbs Racing. This sports trading card is part of the 2018 Panini Prime Racing set and is authenticated with Panini Authentic. The limited print run and serial numbering make it a rare collectible for fans of auto racing and Kyle Busch, adding value to any sports memorabilia collection.