What is the longest bat allowed in MLB?

What is the longest bat allowed in MLB? According to the Official Rules of Major League Baseball [1]: 1.10. (a) The bat shall be a smooth, round stick not more than 2.61 inches in diameter at the thickest part and not more than 42 inches in length. The bat shall be one piece of solid wood.

According to the Official Rules of Major League Baseball [1]: 1.10. (a) The bat shall be a smooth, round stick not more than 2.61 inches in diameter at the thickest part and not more than 42 inches in length. The bat shall be one piece of solid wood.