Today on our 2012 Mazda 5, well be test fitting the Thule Sonic Medium rooftop cargo box, measuring 13 cubic feet in glossy black, part number TH634B. With the Thule Arrowblade podium roof rack system on our vehicle well begin our test fit by placing our box directly onto our load bars. With the feet hanging out of the bottom of the box we can adjust them as necessary to fit around each bar. … see more >