INFINITE's Sunggyu released a teaser photo and the title for his last track on his upcoming solo album, '27.'

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The last track is titled "Reply" and is revealed to be a slow acoustic duet with Park Yoon Ha from season 4 of 'K-Pop Star.' According to the teaser photo, the track is to narrate the deep and unvoiced thoughts that everyone might have at one point in life. 

Meanwhile, '27' is set to drop on May 11.