It isn't obvious from the pictures, or stated anywhere in its description (that I could find), but upon opening the baggie these came in it was immediately obvious that these were 3D printed. If these were expected to hold heavy items, I might be concerned, but for a router or modem that's certainly not a problem.The brackets themselves are intelligently designed, with an upslope at the bottom and ridges to hold the router stable and in place. Both brackets come with adhesive on the back which I didn't use, but seems to be standard foam tape; if you're attaching this to something smooth like glass, plastic, or metal it should be fine. For dry wall, they give you some anchors and screws (which worked great) along with screw covers for appearance sake. (I didn't bother with these since the router will always be covering those holes.)