Wilson 11" Pony League Fastpitch Softball Official ball for Pony League Softball. Super Seam Technology. Compression Controlled Polycore. Optic Yellow Leather Cover. COR: .47 Compression: 375 lbs. Size: 12" Sold in dozens. Super Seam Technology: 20% higher seams. Gives pitchers superior control on the mound and helps fielders locate the ball quicker in the glove and throw with more accuracy. Polycore: Polycore sofballs do not break down during play as quickly as cork softballs making them the most consistent playing softballs available.