I have had one in the back of my vehicle for 35 years. Ever since I was stationed in Germany in the 1970s. I keep it even now and we live in the COLD south!!!!! Freezing rain and snow in Alabama on the way tonight and tomorrow. Thus, I have always kept my emergency kit in the back of the vehicle. We stopped at a car wreck a few months back. Out I went, put on the screaming yellow vest and directed traffic till the police arrived, thanked me and took over.
Bless you for jumping in to help at the accident scene.