Strap it around your waist or wear it across the body. This adidas by Stella McCartney bum bag is about stylish ease and multiple options. Two separate compartments keep essentials organised and accessible, so your phone and keys are always in close reach. The minimalist design makes the bag incredibly easy to style - keep your whole look sleek with a monochrome aesthetic or let the bum bag pop against a clash of patterns and colours. To reduce our reliance on virgin materials, we make sure that our vegan alternatives also contain a minimum of 25% recycled content. adidas Performance.