John Gill Commentary Exodus 27:6

"And thou shalt make staves for the altar, staves of acacia wood, and overlay them with brass." — Exodus 27:6 (ASV)

And you shall make staves for the altar, staves of shittim
wood
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.