SeungHo (승호) Full Name: Yang Seung Ho (양승호)
Date of Birth: October 16, 1987 (1987-10-16) (age 22)
Position: Leader, Vocalist

G.O (지오)
Real Name: Jung Byung Hee (정병희)
Date of Birth: November 6, 1987 (1987-11-06) (age 22)
Position: Main Vocalist
G.O. is a former member of Korean group, TYKEYS, a 3-member band that debuted in 2007.

Joon (준)
Real Name: Lee Chang Sun (이창선)
Date of Birth: February 7, 1988 (1988-02-07) (age 21)
Position: Vocalist

Cheon Doong (천둥)
Real Name: Park Sang Hyun (박상현)
Date of Birth: October 7, 1990 (1990-10-07) (age 19)
Position: Rapper, Vocalist
Cheon Doong (Korean term for Thunder) is the younger brother of 2NE1 vocalist Sandara Park[8]. Having trained under Leon Entertainment, Cheon Doong transferred to J.Tune to then replace member Sang Bae (상배) after he left before the group's debut. Like his sister, he lived in the Philippines and is fluent in Tagalog and is conversational in English.

Mir (미르)
Real Name: Bang Chul Yong (방철용)
Date of Birth: March 10, 1991 (1991-03-10) (age 18)
Position: Main Rapper
Mir is the younger brother of actress Go Eun Ah (Bang Hyo Jin).

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