Indoor balls
Indoor balls are specially designed for use indoors, with less bounce than a normal ball.
Futsal
Since 2002, the KNVB has used the name futsal instead of indoor football. The word futsal is derived from the Spanish words 'futbol' (football) and 'sala' (hall). An official futsal match is played by two teams of five players, the match lasts twice 25 minutes and the pitch is about twenty by forty metres.
Size and weight of an indoor ball
As with any ball sport, there are certain requirements for the ball in futsal too. An official match ball must be size 4, which also means the ball weighs between 400 and 440 grams. The ball contains an absorbent layer, which gives it a weaker bounce. Playing with this so called low bounce ball places greater demands on the technique of the players.
Material of an indoor ball
Footballs are made from wear resistant material, for which polyurethane is used in most cases. Because polyurethane is used, the ball is lightweight and barely sensitive to moisture.