Proenza Schouler’s PS1 bag is a must-have investment in iconic style. Loved by countless A-list celebrities including Mary-Kate and Ashley Olsen, the PS1 bag features buckle straps, a slouchy silhouette and a metallic flip-lock closure.The instantly recognizable PS1 style comes in a clutch, shoulder bag and backpack design. Invest in bold python prints and vibrant colors for a statement look or go for a low-key black or tan style for a stylish morning commute.