Instruction: Evaluate the answerability of a question by analyzing the related document, outputting yes if the document contains information addressing the question, and no otherwise.

Input:
Question: Is this the third generation model with AC variable frequency control
Document: I did have some troubles with the internal gas valve on my earlier (guess 2013) model. Amazon was very helpful in taking back the unit for a full refund.I decided to buy the 2014 model, as it has some improvements - the most impressive is the removal of the amps control from the foot pedal. The foot pedal location was a pain for me. Upon unpacking I found the gas valve to be damaged, noting the box was in perfect condition.
Well worth the money. It works great on 110 or 220 power. Has a smooth arc and starts every time on AC or DC.
Great machine I highly recommend it for a home garage. The 110v and 220v support with a simple plug change is great.\It produces clean welds and on stainless and aluminum it works great. The only feature I would add to a future version isan adjustable frequency from 60 to 240 hertz for aluminum. The fixed 60 hertz frequency works excellent and its quiteto listen to versus my old Miller Econotig Welder. This beats my old worn out Miller by a long mile.
They promptly wrote back the next day, which was a Saturday and answered my question. And they followed up again on a Sunday to make sure my question was answered. Customer service seems to be a priority to this company.The quality of the product seems good, the only issue I saw was the food pedal was a little dinged up upon opening.
OK, I purchased this welder with a little hesitance. I needed to replace my Nationally known blue machine and funds were a little low. After many days of research and watching the seemingly paid for YouTube videos I decided to purchase this machine.
Not ideal but for quick operation  you can at least play with the welder.Set up was pretty easy even though I had to pull the Torch apart to pull the cover over the lines to add a black plastic nut supplied in the box to cover the bare power source connector that was mentioned on &#34;Tig Time&#34; Youtube Channel, took about 10 mins.
It will take sometime to get the pulse dialed to you particular situation if you are an Old School Tig welder but a little bit practice you will be a Pro.Initial start up Arc is good, I welded up some thin wall 4130 and couldn't tell a difference between my old and new welder. Aluminum welded very good also.
It shipped the next morning and I received it 2 days later, proximity being one State away helped. Package was well deigned and Welder was very snug inside and very well packed.After going through all the items in the box and doing a thorough inspection I could not detect any problem except for one very minor detail. The welder comes with a small accessory kit containing 1 tungsten, 2 caps, 3 nozzles, 3 collets and one collet body.
I used one of these machines while visiting my friend's fab shop and was so impressed that I decided to get one for myself. I plan to use the TIG function primarly which is was I tested it with. I still need to setup an outlet in my garage to run this thing which should happen tomorrow. 240VAC is ideal if you can do it. Ahp recommends a 40A circuit at 240VAC if you plan to do any stick welding,but if you're doing TIG only then you only need a 30A circuit.
I purchased this unit to teach myself tig as I already have a miller mig unit. I was highly impressed that the unit arrived 2 business days after I purchased it and it was not in amazon prime for purchase.The power supply on this is smooth. I have been welding 3/16 aluminum and stainless steel exhaust with ease.If you want some reviews on this unit look up Kevin Caron on youtube. He has lots of videos to reference.
Answer: yes