Exodus 27:2

And thou shalt make an altar of shittim wood, five cubits long, and five cubits broad; the altar shall be foursquare: and the height thereof shall be three cubits.

And thou shalt make his pans to receive his ashes, and his shovels, and his basons, and his fleshhooks, and his firepans: all the vessels thereof thou shalt make of brass.

And thou shalt make for it a grate of network of brass; and upon the net shalt thou make four brasen rings in the four corners thereof.

And thou shalt put it under the compass of the altar beneath, that the net may be even to the midst of the altar.