You shall also make is literally “And you [singular] shall make.” This may also be rendered as “You [Moses] have them make.” For it means for the altar. A grating, a network of bronze is literally “a grating a work of net [of] bronze.” This really means “a bronze grating, a network [or, meshwork].” It was probably a kind of latticework with narrow strips of bronze woven together in an open crisscross pattern. The word for grating is related to the word for “sieve,” as in Amos 9.9. Its purpose is not explained, but it was probably intended to hold the burning coals and allow the ashes and grease to fall through to the ground, as well as to allow for a draft of air to pass through from underneath. Both were necessary for a hot fire.

And upon the net refers to the bronze grating. You shall make is identical with the first part of the verse. Four bronze rings uses the same word for rings as in 25.12, 26 and 26.29. At its four corners suggests that the grating may have been flat and square-shaped. Some scholars suggest, however, that it was made like a basket or collar, to fit under or around the outside of the altar. It is more likely that it was placed inside the altar, where it held the burning coals and allowed the air to pass through. The rings were the “carrying rings” (Good News Translation) intended to hold the poles (verse 7), but they were to be attached to the net, that is, to the network of bronze. So we may imagine that this grid had special extensions at its four corners that penetrated through the wooden sides of the altar. This would make it possible for the four bronze rings to be on the outside and still be attached to these extensions of the grid on the inside.

Quoted with permission from Osborn, Noel D. and Hatton, Howard A. A Handbook on Exodus. (UBS Helps for Translators). New York: UBS, 1999. For this and other handbooks for translators see here .