Picked up one of these flashlamps last time I was in IKEA for just £5.

Its a torch, cutter (has an integral blade to cut seatbelts or the like) and glass breaker.
Handy little thing to have tbh- its an led warning device too with magnets to allow you to place it vertical on your steel bodywork and the handgrips have amber LED's inside to flash to warn of your presence on the side of the road etc.
Comes with a neat little holder so I installed it in my boot. I used 2 x short screws to position it.

Careful tho - fuel lines are behind


Positioned here, it does not impede the removal of the car jack bar.

You could install this where your flare goes in the cabin, but it'll fall out of the holder if fitted horizontally. Beside, its bright orange and my cabin is "all black".
......and for £1.99, I got a brolly too - cos we live in Ireland!

