My GT was manufactured in November 2022 and came with a 240v NEMA 14-50P adapter. I used the 120v nine times no problem and the 240v once OK just to check it. Then I installed an Emporia smart wall charger for convenience with an app that tells me precisely the kWh used to charge.
As far as the 14-50 outlet, do not use the Leviton or any other $10 NEMA 14-50 from Home Depot, Lowes, etc. There are countless stories on the Internet about these causing fires when used for EV charging. They're OK for dryers but not EVs. They do not meet code for EV (over 3-hours continuous use). That said, they might be OK for the GT, which only charges at 15 amps on a 50 amp circuit. If you were charging at 48 amps, you'd be asking for trouble with the cheap outlets.
If you want a safe outlet get the Hubbell or Bryant (by Hubbell). These are industrial grade. They can run up to $100 or more but you can get from Grainger for $46.
https://www.grainger.com/product/49YY93
The Emporia is $400, after coupon code take off 5%. No shipping or tax and qualifies for 30% IRS tax credit. Net cost about $266. It's a nice unit, I like it. For $266, not worth screwing around with the Webasto.
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