Review on Glarks Drywall Self Drilling Anchors Tapping: Secure and Easy Installation for Drywall Projects by Ashton Dahmer

Okay, first of all they come with 1" screws with a completely different pitch than drywall or decking screws (which you can still use but they will deform the threaded portion of the anchor and likely weaken) and the anchor itself is not long enough to work with x rock. So if you need to hang something no more than 1/2 inch thick and weighing only 8 or 10 pounds in a 1/2 inch brick they will do, but screw anchors are much better.