Exodus 38:3-7

3He made all the utensils of the altar, the pails and the shovels and the basins, the flesh hooks and the firepans; he made all its utensils of bronze. 4He made for the altar a grating of bronze network beneath, under its ledge, reaching halfway up. 5He cast four rings on the four ends of the bronze grating as holders for the poles. 6He made the poles of acacia wood and overlaid them with bronze. 7He inserted the poles into the rings on the sides of the altar, with which to carry it. He made it hollow with planks.