Race car & trailer got taken out at stop light

What part hit your duster? Looks like his car went under your trailer. Was the Duster that far forward or was that impact related?
Car sits in the very back of the trailer. Impact pushed it all the way to the front. Broke 1 strap and pulled the D ring out on the other side. Looks like since he hit me low the bottom of the trailer door was what actually contacted the car. His car went in about 5 feet and then came back out.