Although they are designed for use in a back-to-back 2-post rack, I use them separately as shelves. They're the best I've found so far. The front and back hems are perfect for securing cables, and they have ventilation holes on the side.
KENUCO Panels Shelves Active Components
6 Review
π© Tripp Lite SRCAGENUTS Cabinet Square Hole Hardware Kit - Rack Enclosure Screws, Washers
7 Review
π¦ StarTech.com 4U Rack Mount Drawer - Durable Steel Storage for 19" AV/Sever/Network Equipment - 55 lb Capacity - 4UDRAWER Black
7 Review
NavePoint 1U Black Vented Rack Tray Shelves - Universal Design, 8 Inches (210mm Deep), No Lip
11 Review