I am new to using a wet polisher grinder. My task was to polish a slab of petrified wood I had purchased multiple years ago in Utah. Reviewing multiple videos on YouTube was helpful in regards to seeing how to use this wet grinder, how long to use particular grit pads, and how the surface should appear at each stage.The first grinder I purchased did not have the pads in it. Whether that was an oversight or otherwise, it went back and I decided to get the ZTE because it was shipped directly from ZTE. “Assembly” was intuitive with all the necessary tools including a hex and open-ended wrench. I appreciated the extra parts for what potential electrical repairs (for the internal carbon brushes), but think it should also have a spare water inlet O-ring. Getting that same O-ring gasket at the proper tightness required it to be screwed down, distorting it slightly. When I finished each day, I relaxed that fitting to allow the gasket to come back to normal shape. I can see it being a potential replacement in time.In operation, the grinder performed well. Pads are easily changed as you move upward to finer and less coarse grits. The speed is adjustable and for petrified wood I used a middle setting. For me, it was important to spend the most time (about two hours) with the coarse 50 grit pad to smooth things out over saw cut variations and cracks in the surface. Fortunately, the original sawing was pretty consistent, something I will look for in future purchases. It is a wet operation, and even with the guard in place, you may get damp. You can avoid getting too wet with adjustment of the water flow. Additionally, I felt safe in the outside wet operation with the GFCI in place on my grounded outdoor electrical outlet.Moving forward to 100-200-400-800-1500-3000, I spent about an hour on the 200 and 400, but after that about 20 minutes each with the higher grits provided that expected mechanical grinding magic producing a high gloss finish. It is difficult to get great pictures showing the high gloss reflections, but they are definitely there.What a fun project producing ideas for finding some more unfinished stone to play with. New hobby!