The size of the manual or hygienic shower head can be found (cf. «Complete»), which is equipped with a shower system. In fact, it implies the size of the working area - the area on which the nozzles for water supply are located. If this area is round or square, its size is indicated by diameter or width, for other shapes - by length.
Big size allows to cover more space at once; on the other hand, more compact models are more efficient, and cheaper, all other things being equal. And hygienic watering cans, taking into account the specifics of their use, by definition are made
small.