Today on our 2013 Kia Optima, we'll be test fitting the Thule Sonic XXL Rooftop Cargo Box, measuring 22 cubic feet in metallic silver, part number TH636S.With the Thule Rapid Traverse roof rack system assembled onto our vehicle, we'll begin our test fit by placing the Sonic directly onto our load bars. With the feet hanging out at the bottom of the box, we can adjust them as necessary to fit… see more >