This wipe-off tray contains metal curls to wipe the soldering tip clean. The advantage of this tray is that the sponge no longer needs to be wetted (always ready for use), cleaning is easier, and the soldering iron does not cool down because of the moisture.
Complete with curls!
About UX: this one has holes on the bottom, which are meant to be covered with little rubber feet, I suppose, but mine came without them, just with holes. So tin pieces accumulated in the bottom escape to my table. For this price it's ok, I think.
Only negative thing I can say about it is size. Somehow I thought it is going to be bit bigger than what it is. But that is just me. If you see parts delivered with even high end soldering irons you do see that you are getting more then fair sized product.
It works good and it is necessary tool when soldering. Sponges thermally stress your iron tip and lower down the temperature very fast. This just cleans your tip. In some stages your tip can't be cleaned by the sponge anymore and this will clean it. For removing of the excess of the tin just lightly stab your soldering iron in it and for cleaning just strike the iron across the top and apply some pressure. Easy peasy.