USB + outlets. I use quite a few smart plugs, and many are pretty big. The spacing is perfect for 4 smart plugs.I bought one to test, and quickly bought another.Now, I don’t use them for laptops or major electronics. There isn’t enough protection for those devices, however, for charging handhelds, no problem.The flat plugs are perfect for plugging in behind furniture. The cord length, though long, provides multiple options.I plan on wall mounting mine soon.I’ll probably purchase a few more to puSee full review