Disclosed herein is a bat comprising a handle portion, a transition portion attached to the handle portion, and a barrel portion attached to the transition portion. The barrel portion includes one or more first cross-sections having a first stiffness and a plurality of second cross-sections having a second stiffness. Each first cross-section is beside one second cross-section or between two of the second cross-sections and the first stiffness is greater than the second stiffness. The variance in stiffness between the first cross-sections and the second cross-sections is created by varying the amount of material in the cross-section or by, more accurately, removing material in the second cross sections to make the second cross-sections more flexible by creating slots. Likewise, a bat may be provided with third cross sections on the sides of the second cross-sections distal from the first cross-section whereby the third cross-sections are less stiff that the second cross-sections because more material is removed.