Looks like DC only. All (pretty sure) TIG welders are DC, and some are also AC for use with aluminum.
The spec sheet for the welder in question does not list AC TIG, so it's aluminum capability is with MIG, DC.
Stick welding can be either AC or DC, rods available to do a fine job with either.

•1951 GMC 250 in the Project Journals
•1948 Chevrolet 6400 - Detroit Diesel 4-53T - Roadranger 10 speed overdrive - 4 wheel disc brakes
•1952 Chevrolet 3800 pickup
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"First, get a clear notion of what you desire to accomplish, and then in all probability you will succeed in doing it..." -Henry Maudslay-