3D printed organization insert my husband made to help from having Dr. Brown bottles from falling over. Inserts are made for either 4oz or 8oz bottles. I have one of each in the container. Diameter is slightly different for 4oz vs 8oz so that’s why there’s 2 sizes and they are labeled so you know which one is which. Genius!! Baby products, newborn LTKKids LTKBump LTKBaby