What plug is this?

[Zorg]

Can I get an adapter for it?

 

[SCW-Greg]

That looks like a really old 10-30 outlet (30amps). But it doesn’t have the L receptacle in the middle like it should. I would have an electriciton confirm the power to that outlet, and consider having it updated to the newer outlet style.

Proper “Gen 2” adapters from Tesla are here:
Model S/X/3 Gen 2 NEMA Adapters

But the outlet should look like this...

 

[Zorg]

My limited Google skills show some form of a 10-50. It's supposed to be a 240V 50A outlet.

 

[Tam]

Can I get an adapter for it?

As @Zorg pointed out, it's a NEMA 10-50:

Hubbell Wiring Device-Kellems 50A Single Receptacle 125/250VAC 10-50R BK HBL7962 | Zoro.com

I don't think Tesla has it.

I wonder if @johnr can customize one for you.

NEMA 10-50 Adapter for Tesla Model S and X Gen 1, 15 ft.

 

[Zorg]

About this? Https://www.amazon.com/Conntek-EV1050T-Adapter-compatible-Vehicles/

 

[brkaus]

10-50 is hot-hot-neutral

A 6-50 is hot-hot-ground

A 14-50 is hot-hot-neutral-ground

The adapter might work, but not sure how they are handling the missing ground? Neither answer is particularly great.

 

[Zorg]

Read somewhere that 10-50 use the same prong for ground and neutral. Not quite following

 

[Feathermerchan]

So if the wiring is 50A hot-hot-neutral, an electrician should be able to rewire the circuit for hot-hot-ground and install a Nema 6-50 which you can but a tesla adapter for ($40). Have him install it with the ground lug up.
I have one for charging at my parents house and it works fine. AFAIK no Tesla adapter uses the neutral.
But some of the Nema plugs require it.

 

[brkaus]

Read somewhere that 10-50 use the same prong for ground and neutral. Not quite following

Ideally, in modern construction, the only place neutral and ground are connected is at the meter and main breaker box.

Any other connection has some moderate risk. Most notable is shock risk if a wire comes loose. Granted, many have survived with the old standards for a long time, they were changed for a reason.