Warning triangle

I use a wheelchair, and I am often worried that people or cars will bumb into the ramp. So I made this warning triangle that packs up flat. It comes with feet to stand on the ground, or with grips that will attach to the ramp. The ramp is 8mm metal and its a snug friction fit.Let me know of other ramp dimensions and I will update with extra models. The triangle itself is 3mm thick if you want to make your own holder.Any filament will do, but I suggest red or orange for visibility.