Trailer Hitch LockTrailer Hitch Lock Bison Products Bison Products Trailer Hitch Lock is a telescopic security post designed to anchor your trailer or caravan to the ground, providing a clear and effective deterrent to theft while parked. Installed by concreting the post into the ground, the unit accepts your existing hitch lock so you can hitch up and lock the trailer to the anchored post. The telescopic design lets the post sit neatly when not in use and extend to