
These are sturdy little shelves with rubber stops on the bottom to prevent sliding and allow for stacking. They are great for hard surfaces like tables or floors. I wouldn't recommend it for thick carpets. I have a vertical rotating media shelf (18 x 34 squares and 5ft high) that has been filled. The shelf is perfect for a small space, so I was looking for a way to expand it. I bought four of these little guys not expecting much, but they fit perfectly on my other L-shaped rack, back to back, leaving about 2 inches from the edge. They don't slip or wobble when I add or remove drives and (4 racks) is a stable 56 drive expansion. I tested the installation on top of each other and it was still stable so I immediately ordered 4 more to make a 2nd row and add 112 to my rack. It's a solid extension.

Large Waterproof Cable Organizer Bag For Travel, Universal Electronics Accessory Holder, Portable Gear Carry Case For Cables - Black
28 Review

2 Pack GLCON EVA Carrying Cases - Small Electronic Case For Earbuds, Earphone, Charger & More - Shockproof Exterior & Portable Storage Pouch Bag - Blue
24 Review

Elago AirPods 2 Dust Guard Cover - Gold, US Patent Registered - Compatible With Apple AirPods 2 Wireless Charging Case
27 Review

Universal Electronics Accessories Organizer Bag - Waterproof Portable Cable Travel Gear Carry Bag (L, Black/Pink)
27 Review