The best application for this TurboCord unit is for AV to get automakers to include it with their vehicles that include 3.3kW on-board chargers. Then, installing the NEMA 6-20 outlet at home makes sense. If you already have a dedicated 120V outlet in your garage, there's a chance it could be re-wired to 240V for this unit. However, it requires 12ga wiring and I don't know how common that is. In addition, most garage outlets are daisy-chained from a single circuit breaker which would also prevent 240V conversion.
I noticed that the User's Manual for the 240V version specifically prohibits the use of ANY AC adapters. That makes it nearly useless in the wild. NEMA 6-20 is extremely rare in any application near a parking space. The only common application is Motel A/C units. IMHO, a Clipper Creek LCS-25 with adapters to NEMA 14 and NEMA 10-30 is a much better low cost solution for trips to "grandma's house".
This unit has also occupied the banner ad space at the top of this site for the last several days that I've visited.