Wilson Fastpitch Softballs...Quality And Performance! Wilson 47 COR Girls Fast Pitch Synthetic Softballs Feature: Cover is frequency-matched optic yellow synthetic Super Seam TechnologyATM has 20% higher seams for maximum control Red stitching Center is compression controlled cork COR: .47 max. Compression: 375 lbs. max Models: A9106B: Size: 12", A9306B: Size: 11", Wilson Fastpitch Softballs...Maximum Control!