Lija I bet they are something similar to these

Storage Dynamics 5-Foot Vinyl Covered Steel Over door Storage Basket Rack: Closet Storage And Organization Systems: Amazon.com

Amazon.com: ClosetMaid Adjustable 8-Tier Wall and Door Rack, 18-Inch: Home & Kitchen

I just have mine turned around so the shelf is open towards me and the lip acts as a back for the cups to not fall through...