A Curtain Van or Curtainside Trailer is generally a flatbed with an upper structure installed to the flatbed as a tarping system. This system works very just like an accordion or as a curtain. When pulled forward, the tarp exposes the flatbed offering access to for side, rear and overhead loading. Curtainside trailers are often called Tautliner.   Disclaimer Our content is not in any way legal advice or binding. The information provided by might not be the official legal or full definition. Also when pursuing a specific transaction you are encouraged to conduct your own due diligence and to consult legal counsel as appropriate.