Adidas By Stella McCartney Gym Sack Backpack New With Box Adidas ID: GL5451 MSRP $130 Make the most of it: the day, your workout, your time off. The adidas by Stella McCartney gym sack helps you do just that. Spacious and lightweight, the versatile bag transforms into a bum bag when you just need a few essentials with you. Coming back home with more than you left with? Expand it into the backpack and comfortably carry it all. This product is made with Primegreen, a series of high-performance recycled materials. 100% recycled polyester plain weave Carry handles and shoulder straps Converts to bum bag Material: 100% recycled polyester plain weave