*UPDATE* I contacted vevor, they wanted pictures and video of the malfunction. Ahh okay I took a time lapse video of it falling. Then I was asked if the "pressure relief valve" was closed. You mean the dump valve and yes it is. Then I was asked how the seal behind the "pressure relief valve" looked. The seal behind the dump valve looks good and is seated properly. Said the video that I sent didn't show any problems. They're just stringing along until the return window is over. Besides the horrible translation and no knowledge of the product I'd save yourself the hassle and order a jack from a reputable supplier. I received the jack a few days ago and it is identical to the one it is replacing. Identical even down to the jack bleeding off within a few minutes. Yes I filled the reservoir, I cycled the cylinder through its full range. I put a level on the top of the lift arm to see if it would move overnight. Lol it only took a few minutes to be all the way compressed. It is junk.