Louisville Slugger set out to create the lightest-swinging one-piece alloy bat on the market, and that's how the Solo 617 was born. New to the LS BBCOR lineup this year, the Solo 617 is built with an SBC Speed Ballistic Composite End Cap that is 50% lighter than our standard BBCOR end cap, resulting in the ultimate strength to weight ratio in this bat. The -3 bat that swings like a -5.