What does 1 Chronicles 12:20 mean?

When David went to Ziklag, these men from Manasseh joined him: Adnah, Jozabad, Jediael, Michael, Jozabad, Elihu, and Zillethai. They were all commanders in the army. 1 Chronicles 12:20 - Modern Text Bible

(This verse lists the leaders from Manasseh who joined David at Ziklag. Their arrival strengthened David's forces.)