Please note: Amazon have since adjusted their item description since I wrote this review, so skip to last paragraph if you have 4cm thick doors!
I have found it extremely difficult to find overdoor hooks for 4.5cm thick doors, as everywhere seems to sell them up to 4cm thick only. When I found these, I was elated! However, since receiving this item, I have discovered that the item is falsely described. These hooks are only 4cm wide, so will NOT fit doors up to 4.5cm thick. The packaging it came in was pretty awful too, they use a waste of cardboard for such a small thing messily taped up with brown tape. I won't be ordering from Betterware again.
Although it pains me to promote this company or anything they sell, if your doors are up to 4cm thick, I can tell you that these hooks are a very simple design: plain silver, and quite thin, so you shouldn't have trouble getting them between the door and the frame when the door's shut. Nothing particularly 'pretty' about them, just for the simple and practical home!