This field contains the categories (stars)obiektu. The value is multiplied by 10.
You can use this box indicating the intervals in warunkach zapytania. Range is defined {FROM} {FOR}, for example, range from 2.5 stars to 4:
<conditions> <obj_category>25:40</obj_category> (...)
from 3 stars
<obj_category>30:100</obj_category>
maximum 5+
<obj_category>0:55</obj_category>