Rule

One-wall · Rule 2.4 Uniform

General

All parts of the uniform, consisting of a shirt, shorts, socks and shoes, must be clean at the beginning of a match. Only customary handball attire, in the referee’s judgment, can be worn. Shirts must be full length, not cut off in the torso.

1.) Shirts are not required for outdoor play unless requested by opponent or referee.

2.) Sleeveless shirts are allowed until such time as the referee deems it necessary to help keep the floor from getting wet, then the player must change to a dry shirt.

Mentioned here

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