Numbers 7:3-9

3They brought as their offering before the LORD six covered carts and twelve oxen—an ox from each leader and a cart from every two leaders—and presented them before the tabernacle.

4And the LORD said to Moses, 5“Accept these gifts from them, that they may be used in the work of the Tent of Meeting. And give them to the Levites, to each man according to his service.”

6So Moses took the carts and oxen and gave them to the Levites. 7He gave the Gershonites two carts and four oxen, as their service required, 8and he gave the Merarites four carts and eight oxen, as their service required, all under the direction of Ithamar son of Aaron the priest. 9But he did not give any to the Kohathites, since they were to carry on their shoulders the holy objects for which they were responsible.