Indoor hockey is a 5-a-side variant, using a field which is reduced to approximately 40 m × 20 m (131 ft × 66 ft). Although many of the rules remain the same, including obstruction and feet, there are several key variations: players may not raise the ball unless shooting at goal, players may not hit the ball, instead using pushes to transfer it, and the sidelines are replaced with solid barriers, from which the ball will rebound and remain in play.[5] In addition, the regulation guidelines for the indoor field hockey stick require a slightly thinner, lighter stick than an outdoor one.[6]