In football, a pair of poles covered with a bright orange padding and connected by a 10-yard chain that are used to measure first down distance from the line of scrimmage.
In professional football, each of the poles known as the "sticks" is covered by a bright orange padding, shaped like a downward facing arrow with a target symbol at the top, and are operated by individuals who are part of the "chain crew." Both poles are placed on the sidelines, with one pole set at the line of scrimmage, while the other is placed at the first down yard mark. In order to keep the measurement accurate, there is usually a clip attached to the chain at the five-yard mark. The down indicator box, which displays the current down, accompanies the first of the sticks and marks the current line of scrimmage.
When a play requires measurement by an official, the chain crew will be called upon to bring the sticks onto the field to determine whether the play has resulted in a first down.
In professional and college football, an auxiliary chain crew on the opposite side of the field holds an additional pair of sticks and down indicator for player and team reference during play.