
1) Auto attachment 2) Expedition extra 3) How bikes go by car 4) It might carry a canoe
Found on
https://www.crosswordclues.com/clue/roof-rack

A roof rack is a set of bars secured to the roof of a motor car. It is used to carry bulky items such as luggage, bicycles, canoes, kayaks, skis, or various carriers and containers. There is a long history of the use of roof racks and their designs. They allow users of an automobile to transport objects on the roof of the vehicle without reducing ...
Found on
http://en.wikipedia.org/wiki/Roof_rack

A metal or plastic device attached to a vehicle that is used to anchor cargo to the vehicles roof.
Found on
http://www.edmunds.com/glossary/
No exact match found.