What does Numbers 4:15 mean?

When Aaron and his sons finish covering all the holy things and the camp is ready to move, the Kohathites can come and carry them. But they must not touch the holy things themselves, or they’ll die. These are the things the Kohathites are responsible for carrying from the tent of meeting. Numbers 4:15 - Modern Text Bible

(Only after the priests have packed everything can the Kohathites carry it. Touching the holy objects directly is dangerous, so there are strict boundaries.)