Women's lacrosse is played with a team of 12 players, including the goalkeeper during usual play. The ball used is typically yellow, unless both teams agree to use a different colored ball. It is usually yellow because it makes it easier for people to see the ball in the air and in another player's stick. The duration of the game is 60 minutes, with two halves. Halftime is ten minutes (colleges use fifteen) unless both the coaches agree on less than ten minutes prior to the start of the game. Each team is allowed two 90-second team time-outs per game (two 2-minute timeouts in the USA). In the US, a time-out may be requested by the head coach or any player on the field after a goal is scored or any time the requestor's team is in clear possession of the ball. If a possession timeout is called, players must leave their sticks in place on the field and return to that same place for the restart of play. No substitutions are allowed during this stoppage of play.