Numbers 7:5

2 Then the chiefs of Israel, the heads of their fathers' houses, made offerings; these were the chiefs of the tribes, who were over those who were numbered.

3 And they came with their offerings before the Lord, six covered carts and twelve oxen; a cart for every two of the chiefs, and for every one an ox.

4 And the Lord said to Moses,

5 Take the things from them, to be used for the work of the Tent of meeting; and give them to the Levites, to every man what is needed for his work.

6 So Moses took the carts and the oxen and gave them to the Levites.

7 Two carts and four oxen he gave to the sons of Gershon for their work;

8 And four carts and eight oxen he gave to the sons of Merari for their work, under the direction of Ithamar, the son of Aaron the priest.