All good except I wish it would give the option Fahrenheit/Celsius and not just Celsius. Oh well just print a conversion chart laminate it and you are good to go.

TL;DR -- Slightly over-priced for what you get and it does work, but the transducer does not produce the rated power.

I bought the 40A model, which purports to have a 200 watt tank heater and a 240 watt transducer. I put an ammeter on it to test this, and while the heater makes the rated 200 watts (120V @ ~1.9 amps), the transducer only makes about 200 watts (120V @ 1.75 amps). Curiously, this would match the specs for the 30A unit (although the label on this one does say 40A).

The usable tank volume is approximately 11.5" x 9.25" x 4.75" (WHD), which is 505 cubic inches, or 2.2 gallons (~8.3 liters). I'm assuming you're not supposed to fill it past the ridge that's about 1" down from the top. The entire tank volume might be 2.6 gallons (10 liters), but the usable tank volume is not. You're not supposed to set objects on the bottom of the tank, so the included basket further reduces the usable volume of the tank.

The 200 watt heater took over 30 minutes to raise the temperature from 20C to 40C. I didn't do the math to determine how long it should take to raise 2 gallons by 20C degrees, but when you're waiting for it, it's slow. Glacially slow...

The controls work OK, but the front panel of the unit is thin sheet metal, and flexes quite a bit as you're pressing buttons. The manual is what you'd expect from a typical Chinese manual; hard to read and lacking clarity. For instance, if you don't have enough water in the tank, the temperature blinks '01' and although the heater indicator is on, it's not actually heating. You do need to fill the tank a little more than 3/4 full before it decides it has enough fluid to be happy.

When the unit is first turned on, the timer defaults to 5:00 minutes. Once the cycle has completed, it resets back to 0:00. This is a little annoying if you want to run a number of cleaning cycles. I had to keep resetting it to 15 minutes before starting each cycle.

I have no way to measure the transducer frequency, so I'll have to trust that it's indeed 40KHz. The unit is not excessively noisy, but you don't want to run it in your office. It produces a moderately loud buzzing, which is the tank resonating at some frequency.

My overall impression is that I would have found it to be a much better value at $150 than $200. It does clean things; I had a bunch of fairly dirty sockets from a socket wrench set, and it cleaned them up. I used AIM Purple Dragon cleaner, and they came out pretty well. I also cleaned a few bolts from an engine that were greasy and had some rust, and it did OK on those. It's good enough to not return it, but it's no value deal. That being said, I didn't see any other units on Amazon that seemed any better.

The ATV had been sitting outside behind this guy's garage for 15 years, had not been run for just as long. The owner gave it too my grandkids and Pa Paw got to see if he could fix it, I took the carburetor off to rebuild it, it was so gummed up the throttle slide would not even begin to move, the bowl and float were just as bad. I bought carb cleaner from auto store, soaked the carb for 4 days , it didn't do anything to the gummed up carb, then I purchased this ultra sonic cleaner wit a gallon of the automotive soap cleaner. I mixed up the solution and placed the carburetor disassembled of course into the fluid. I turned the unit up to the highest heat level and ran the unit for 3 - 30 minute cycles. I am really happy with the job it did on the carburetor

Perfect for rebuilding motorcycle carbs!

Using this for my shop cleaning motorcycle parts... even with light degreaser it works well. Well made..