The newest design from the Milan-based luxury leather-goods brand Valextra—whose iconic fans have included Gianni Agnelli, Jackie and Aristotle Onassis, and Grace Kelly—presents a stylish alternative for the jet-setter’s duffle. The new unisex Polyhedral bag ($3,400) easily collapses and re-forms at its indented folds, making it an ideal spare travel sack. The functional design is fitting for the nearly 80-year-old brand, whose name is a portmanteau of the words valiglia (Italian for suitcase) and extra.

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