I bought three items, but all complaints came with defective items. After installing, it was a little over a month and I got a doorknob and a seat. Spot welding at the joint was weak, and it was a temporary fixation, so it could be removed with vibration. Here, we welded the joint part semiautomatically, and all it has been reattached. The quality of the product is no problem elsewhere, but the thing that the door knob will raise is only a fatal defect. As a method of improving the product, if it seems there is a limit to the inspection of spot welding, after inserting the door knob, return the inserted collar and try strengthening ... the extent that it repaired and reattached to the site, the warranty I want to get it. . .