Dubbel Duffel pop-up

174 Grand St at Bedford Ave, Williamsburg, Brooklyn. Subway: L to Bedford Ave. Shop the entire collection of two-in-one expanding bags from this 35-year-old American company, inside GGrippo art and design studio. Top picks include large mesh duffel bags ($198) with removable shoulder straps that unzip to twice their size, and nylon fanny packs ($138) that transform into adjustable padded backpacks.