someone help me figure out how he got this sound on his vocals

[jAudio]

can someone let me know how he made that autotune harmony type sound on his vocals i hear it alot on a bunch of hit records.
especially when he says "i cant rock wit you no more"
https://www.youtube.com/watch?v=mq_92lou2d8&index=1&list=PLX1YlxaW6Mxd_TugFItRHa5bYEqqDhiU0

 

[rhythmgj]

Multi-tracked vocal (sing it again).

GJ