Numbers 4:31-33

31And this is the charge of their burden, according to all their service in the tent of meeting: the boards of the tabernacle, and the bars thereof, and the pillars thereof, and the sockets thereof, 32and the pillars of the court round about, and their sockets, and their pins, and their cords, with all their instruments, and with all their service: and by name ye shall appoint the instruments of the charge of their burden. 33This is the service of the families of the sons of Merari, according to all their service, in the tent of meeting, under the hand of Ithamar the son of Aaron the priest.