Modern insulation with a traditional knitted look. For the Men's Shackleton Jacket , Jack Wolfskin have given their popular medium-weight fleece a traditional patterned look. Naturally it has all the typical advantages of Jack Wolfskin's Nanuk fleece fabric: It is warm, very breathable and wicks moisture quickly to the outside. The Men's Shackleton Jacket can be worn as part of a layering system. You can also wear it as an insulating outer layer in non-windy conditions.