They are made by Race Ramps - Car and Auto Ramps for Service, Loading and Display - Race Ramps
They can even make custom ramps if needed
Guys, if you are going to use your trailer a lot, or just don't want to deal with the heavy ramps, you need to check these things out. A little spendy, but I got to see them in action recently, and if I had an enclosed trailer or one low enough to use wedge ramps, these would be a serious contender.
@V-SHOT, you agree?