Urethane Coverstock Rhino Pro 2-Piece Symmetric Core 16 lb 15 lb 14 lb 13 lb 12 lb RG 2.55 Diff 0.015 Length 69% Flare 0% Open in Layout Lab Factory Finish: Sanded Similar Bowling Balls Compare at weight 12 lb 13 lb 14 lb 15 lb 16 lb Compare Black Grenade Urethane Sanded Grenade RG 2.550 Diff 0.020 Rack Attack Pearl Rack Attack Pearl 500 Siaair Micro Pad, Royal Compound, Royal Shine Rack Attack RG 2.542 Diff 0.024 Rack Attack Solid Rack Attack Solid 500, 4000 Siaair Micro Pad Rack Attack RG 2.542 Diff 0.024