What type of diesel is this?

What type of diesel is this? Is this an SW- something?

https://www.reddit.com/r/trains/comments/ctg8td/palmetto_railways_in_charleston_sc/?ref=readnext

This is my second winter in Charleston, and this engine, based at the waterfront yard nearby, is the cleanest, most immaculate active locomotive I have ever seen! I pass there often, and I have never seen the engine ever look less than 100% perfect.

It’s an EMD SW1001. This unit was originally South Carolina Public Railways (SCPR) #1001 built in April 1975. The Railway changed its name to Palmetto Railways in 2013.

Thanks!

Interesting that they gave it the number 1001.

Unreal condition for a 45 year old engine. I was watching it switch this morning, close up at a grade crossing. It looks perfect even from 15 feet away. Sounds great also. The RR is obviously proud of it.