BSS – the special sub-unit of SEVENTEEN – is officially releasing their first single album, SECOND WIND. BSS stands for BooSeokSoon and is comprised of three SEVENTEEN members: SEUNGKWAN, DK and HOSHI. This first release contains a CD, Outbox, Photo Book (88 pages), Lyric Book (8 pages), Photo Card (random 2 of 6), Sticker, Habit Tracker Mini Card (random 1 of 3), BSS Mini Card (random 1 of 3) and Folded Poster. NA Retail Exclusive: Postcard (random 1 of 3). Dimensions: 185 x 156 x 16 mm.