Jenkins: How multi-configured projects run on a specific node without using labels?

[peterl...@gmail.com]

The person who configured Jenkins left company. I am confused with the Jenkins settings. In the current Jenkins setting, many multi-configuration projects run on slave01. The labels of slave01 is "slave01 flyweight". But, in these multi-configuration project configurations, I cannot find the check box "Restrict where this project can be run". I do not understand how these multi-configured projects run on slave01 without restrict to the label (flyweight)?