This is an iPad Tripod Mount Remix with a press fit for a 1/4"x 20 standard nut. It can be tapped in with a hammer or a squeezed down with pair of channel pliers. The nut will fit a standard tripod thread. The nuts are about 3 cents at Home Depot.
I am using my 10.5" iPad with it in a silicone cover which grips the insides of the mount so good you can almost turn it upside down before it falls out. The width of the mount is 10 mm so other thin iPad covers might fit but may not grip as well if it is tilted over 90 degrees. The silicone covers are more soft and sticky.
This is my 3rd revision of the mount, the first model was using a tab and a nut on top. The 2nd version had the embedded nut with chamfered edges (.stl not included) which was nice but I did a 3rd revision with fillet edges and I think that looks the best.