I tracked this down 2 years ago. they were made by Uhaul only. They will never sell one because it makes finding stolen units almost impossible for the police. They want police to know that if you can't produce a rental agreement, it is HOT. I even offered if we could do a group buy of all existing units (they no longer produce them and in many areas are reluctant to rent them...there seems to be a problem with them cracking when one traveles from high elevation to lower elevations (in particular, the Rocky mountains)).