Park Jae-hyung (Hangul: 박제형; born on September 15, 1992), also known as Jae, is a Korean-American singer, musician, songwriter, and composer. He is the lead guitarist and vocalist for South Korean rock band DAY6 (Hangul: 데이식스), and is a major contributor to the composing process. In addition, he also releases solo music under the name eaJ.