I have a Tesla Portable Electrical Charger in new condition for sale. It includes a carrying case and comes with two interchangeable adapters to plug into different electrical outlets. The cable is 20 foot long and I have used it for about 10 months.
Charging at home costs only $0.15 per kilowatt vs. the cost per kWh at a Tesla Supercharger which can vary significantly, but a common average is around $0.25 to $0.28 per kWh ...or higher depending on location, time of day, and demand. I didn't drive my Tesla much so other than one time, I charged my Tesla Y at home and this mobile charger worked just fine. It was very convenient and effortless to charge in the garage.