Numbers 4:23-26

23You must number them from thirty years old and upward to fifty years old, all who enter the company to do the work of the tent of meeting.

24This is the service of the families of Gershonites, as they serve and carry it.

25They must carry the curtains for the tabernacle and the tent of meeting with its covering, the covering of fine leather that is over it, the curtains for the entrance of the tent of meeting,

26the hangings for the courtyard, the curtain for the entrance of the gate of the court, which is around the tabernacle and the altar, and their ropes, along with all the furnishings for their service and everything that is made for them. So they are to serve.