Second Wind is the debut single album by BSS, a sub-unit of the South Korean boy band Seventeen.

[9] On February 2, BSS teased the single album's three-song tracklist through a highlight medley designed to mimic a fitness app's goal tracker progression.

[12] On February 23, BSS shared a special performance video of the track "7PM", featuring Norwegian singer Peder Elias.

[13] Lee Ha-na of Newsen commended the album for "breathing a new wind into the music industry" with its charming ability to transform into a "support group that is always by your side".

[15] In a review for NME, Tanu Raj scored Second Wind four out of five stars, noting the album as the "perfect pick-me-up" and "a record that exudes endless, sunny optimism".