Car accessory (6)
(Other definitions for hubcap that I've seen before include "Metal protector for car wheel" , "Vehicle wheel trim" , "Metal cover on wheel" , "Wheel attachment" , "Cover on a car wheel" .)
(Other definitions for roof rack that I've seen before include "Carrier for holding luggage on top of a car" , "Frame" , "Attachment to car" , "Framework for carrying things on car roof" , "Framework for carrying luggage on top of car" .)
(Other definitions for radio that I've seen before include "listening device" , "MW, LW or FM sound source" , "Electronic receiver" , "send a message" , "Transmit" .)