This ball is a rare one, indeed.  Introduced by Cochrane in 1917, the Challenger XL with a basket weave pattern was originally finished in white paint as can be seen in early advertisements. This example has a basket weave pattern only it is painted in checkerboard style. The auctioneer believes the paint on this ball is original, and guarantees the ball as genuine. 

Dark brown gutta percha is clearly visible across its cover and there is a small crack in the square above the "R" in "Challenger."  Gutta percha is highly inelastic.  It is far more prone to cracking than it is to stretching.  The modern rubber used to make the covers on fake examples of this ball does not crack.  While this ball shows evidence of use, it is a remarkable ball and one that would fit any serious ball collection.  The auctioneer has not seen another genuine checkerboard painted ball, but, again, has no doubt that this ball is the real deal. A real find.