This black crewneck sweater from Andersen-Andersen is part of their Sailor line.
Andersen-Andersen
Auralee
Berner KüHl
Tcc
American Trench
Howlin'
COMME des GARÇONS
Jil Sander
A.P.C.
Nili Lotan
Batoner
La Paz
Carhartt WIP
Libertine-Libertine
Maison Margiela
J.L-A.L
Ymc
Stockholm Surfboard Club
Arte Antwerp
Rier
Mhl By Margaret Howell