The lightweight Nuna® flex stroller frame works with PIPA™ series newborn car seats to provide swift and easy transitions from car rides to walks. As babies get older, you can swap out the infant car seat for the reversible, toddler-friendly flex seat (sold separately). Either way, the stroller will have you more than ready to take on the world, with its sturdy carbon fiber–reinforced frame, never-flat tires, all-wheel suspension and large storage basket.