Charles Ellicott Commentary 1 Chronicles 11:39

"Zelek the Ammonite, Naharai the Berothite, the armorbearer of Joab the son of Zeruiah," — 1 Chronicles 11:39 (ASV)

Zelek the Ammonite. —Many of David’s warriors were foreigners. (Compare “Uriah the Hittite; ” “Ittai the Gittite; ” and “Ithmah the Moabite,” 1 Chronicles 11:46.)

Berothite. —Of Beeroth in Benjamin (Joshua 18:25).