That is due to oil barrier. I like That concept, would like I'd thought of it!! Even so, that is, I now 3D print cat food bowls which have a really compact, canted inward oil ring, which prevents kittie's fur from accidentaly acquiring oily. It works very well and is https://dallastkvfo.wssblogs.com/36184180/pet-shop-uae-an-overview