Strike King features a new symmetric performance core design matched up with a new, more aggressive SK13 reactive coverstock to provide a significant improvement in overall ball performance for the Brunswick entry level product line. Oustanding shelf appeal Excellent performance Incredible value to entry level balls buyersl 12# RG 2.630 Diff .028 13# RG 2.630 Diff .026 14# RG 2.588 Diff .028 15# RG 2.578 Diff .028 16# RG 2.578 Diff .026 Entry Level Ball WWRD: 05/13/13