I put three triangle reflectors, a refletive vest,tow strap, battery cables, first aid kit, flashlight and a fire extingisher in every vehicle. I unfortunatly have had to use the items several times though fortunatly not always for my vehicle.
I know you asked about the reflectors but what I have used the most is a fire ext. I have put out fires on Buses x2 ,army jeep, army deuce and a half, van, cars x3, cargo trailers x2 and an air force C 127. I was driving the army jeep and one of the buses, passanger in the plane. The rest I passed on the highway sometimes going the other direction. There is a very short period of time to put out a tire or engine fire - wait for a fire truck and it is usually too late to save anything. Only had to get people out one time three toddlers and a baby. Undoing a car seat when you cannot see your hand in front of your face is not fun.
I had people say they would never themselvs be able to use these things even if they had them. So hand the extinguisher to the young guy/gal, same for the first aid kit or the reflectors. Here kid go put on this vest to go set these trianagles out to warn/slow down the other drivers. I will hold the flashlight when you get back while you change the tire.
US Army Retired X 2 (Both wife and I)
2012 North Trail TT 30QOK
2005 Dodge deisel 2500 HD, shortbed, 6 speed manual, Equalizer Hitch, Warn Winch, highlift jack, Honda Gen Set, Winona Canoe