Numbers 7:3-7

When they brought their offering before the Lord, six covered carts and twelve oxen, a cart for every two of the leaders and an ox for each one, then they presented them in front of the tabernacle.

Then the Lord spoke to Moses, saying,

“Accept these things from them, that they may be used in the service of the tent of meeting, and you shall give them to the Levites, to each man according to his service.”

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

Two carts and four oxen he gave to the sons of Gershon, according to their service,