Numbers 7:4

2the princes of Israel, the heads of their fathers’ houses, gave offerings. These were the princes of the tribes. These are they who were over those who were counted;

3and they brought their offering before the LORD, six covered wagons and twelve oxen; a wagon for every two of the princes, and for each one an ox. They presented them before the tabernacle.

4The LORD spoke to Moses, saying,

5“Accept these from them, that they may be used in doing the service of the Tent of Meeting; and you shall give them to the Levites, to every man according to his service.”

6Moses took the wagons and the oxen, and gave them to the Levites.