Exodus 27:6
"And thou shalt make staves for the altar, staves of shittim wood, and overlay them with brass."
Cross References (ranked by relevance)
Exodus 30:4
And two golden rings shalt thou make to it under the crown of it, by the two corners thereof, upon the two sides of it shalt thou make it; and they shall be for places for the staves to bear it withal.
Numbers 4:44
Even those that were numbered of them after their families, were three thousand and two hundred.