A rounded, solid wooden or hollow aluminum bat. Wooden bats are traditionally made from ash wood, though maple and bamboo is also sometimes used. Aluminum bats are not permitted in professional leagues, but are frequently used in amateur leagues. Composite bats are also available, essentially wooden bats with a metal rod inside. Bamboo bats are also becoming popular.

In 1990, Bruce Leinert came up with the idea of putting an axe handle on a baseball bat. He filed a patent application for the 'Axe Bat' in 2007 and the bat started being used in the college and pro ranks over the following years. In 2012, the Marietta College Pioneers baseball team won the NCAA Division III World Series using axe handled bats.[2] Several Major League Baseball players have adopted the bat handle including Mookie Betts, Dustin Pedroia, George Springer, Kurt Suzuki and Dansby Swanson.[3][4]

Baseball bats are made of either wood, or a metal alloy (typically aluminum). Most wooden bats are made from ash. Other woods include maple, hickory, and bamboo. Hickory has fallen into disfavor over its greater weight, which slows down bat speed, while maple bats gained popularity[5] following the introduction of the first major league sanctioned model in 1997. The first player to use one was Joe Carter of the Toronto Blue Jays.[6] Barry Bonds used maple bats the seasons he broke baseball's single-season home run record in 2001, and the career home run record in 2007.[6] In 2010, the increased tendency of maple bats to shatter has caused Major League Baseball to examine their use, banning some models in minor league play.[7][8]

The bat's form has become more refined over time. In the mid-19th century, baseball batters were known to shape or whittle their own bats by hand. This allowed there to be a wide variety in shape, size, and weight. For example, there were flat bats, round bats, short bats, and fat bats. Earlier bats were known to be much heavier and larger than today's regulated ones. During the 19th century, many shapes were experimented with, as well as handle designs. Today, bats are much more uniform in design.
For starters, we should clarify just what we’re talking about when we say fungo bat. Longer, lighter and thinner than a regulation bat (but a larger barrel), a fungo bat is typically 35 to 37 inches long, and weighs between 17 and 22 ounces. As David Allison wrote in the June 1978 edition of Country Journal, “A fungo bat looks to be a cross between a baseball bat and a broomstick.”