These small bowls range in size from 2.5-7" in diameter. The larger bowls are embedded with a keyhole and hang with a single screw. The smallest pieces (see image) are embedded with a screw and go straight into the wall, making placement up to you!
If you need a template, let me know. I have installed hundreds of these little guys... very easy. 
Sold as a set of 14.
Image 1 is in a space of 28" x 16"