Exodus 27:6

“And thou shalt make staves for the altar, staves of shittim wood, etc.] Like those that were made for the ark, and for the same purpose: and overlay them with brass; with plates of brass, whereas those for the ark were overlaid with gold.”

“staves . . . rings--Those rings were placed at the side through which the poles were inserted on occasions of removal.”

“(Compare Exodus 38:1-7.) The great altar which stood in the court immediately in front of the tabernacle was commonly called the altar of burnt-offering, because on it were burnt the whole burnt-offerings, and all those parts of the other animal sacrifices which were offered to the Lord. It was also called the brazen altar, because it was covered with bronze, in distinction from the golden altar or altar of incense Exodus 39:38-39; Exodus 40:5-6. Exodus 27:2 His horns shall be of the same - These horns were projections pointing upward in the form either of a small obelisk, or of the horn of an ox. They were to be actually parts of the altar, not merely superadded to it. On them the blood of…”

“staves for the altar: Exo 35:13-15, Exo 30:4; Num 4:44 Exodus 27:7”

“The poles were to be made of acacia-wood, and covered with brass, and to be placed in the rings that were fixed in the two sides for the purpose of carrying the altar. The additional instructions in Exo 27:8, "hollow with tables shalt thou make it, as it was showed thee in the mount" (cf. Exo 25:9), refer apparently, if we judge from Exo 20:24-25, simply to the wooden framework of the altar, which was covered with brass, and which was filled with earth, or gravel and stones, when the altar was about to be used, the whole being levelled so as to form a hearth. The shape thus given to the altar of burnt-offering corresponded to the other objects in the sanctuary. It could also be carried about…”