Collapsible Solar Traffic Cone
I’m not sure whether most people would place a traffic cone in their car since that would take up precious boot space, but for those who want to make sure that they warn motorists in advance of a broken down vehicle, then the Collapsible Solar Traffic Cone would make sense. After all, it comes with a built-in rechargeable battery and solar panel that will harness the power of the sun to juice up its red LED, attracting attention even in pitch black darkness of the night, while the bright orange color ought to do its job well enough during the day. Being collapsible also makes it easy to store, and you can get it for $55 a pop.
Product Page via TRFJ