A readily movable barrier designed to delineate the outfield boundary in baseball or softball fields, allowing for flexible field configurations. These barriers often consist of lightweight materials such as nylon netting, vinyl, or flexible plastic supported by metal or composite poles. An example is a youth baseball league utilizing a smaller field for younger players, necessitating the temporary placement of a boundary to ensure fair play.
These adaptable structures provide several key advantages. They enable the creation of appropriate playing dimensions for different age groups or skill levels, promoting player development and safety. Historically, leagues adapted existing fields, often resulting in unsuitable dimensions. The advent of these adjustable boundaries allowed for equitable competition across varied field sizes, enhancing the overall sporting experience and minimizing the risk of injury associated with oversized or undersized outfields.