Jae Park, otherwise known by his Korean name Park Jae Hyung (박제형), is a former vocalist and electric guitarist for the band DAY6. He was born in Buenos Aires, Argentina, raised in Long Beach, California and is currently based in South Korea. Prior to joining DAY6, he gained attention as one of the final six finalists of the first season of the singing competition television series K-pop Star.

From 2017 to 2018, Jae regularly uploaded vlogs to his YouTube channel JaeSix, but now uses that platform to release his solo music. Additionally, in 2020, Jae would stream and play gaming content mostly on his Twitch channel, and according to Jae, he does this for a hobby and a way to detox.

On December 31, 2021, Jae announced he had terminated his contract with JYP Entertainment and would be taking a break from DAY6. JYP’s contract with DAY6 expires in 2022 and they will most likely return independently after their military hiatus.

On April 8, 2022, eaJ officially debuted as a soloist with the pop-rock single “Car Crash,” released with an accompanying music video produced by 100 Thieves.