The first profile is a remix of Tosh's floating picture frame that allows more easily for a screw when mounting to a wall. However you can still use a push pin. Design is exactly the size of a traditional 4"x6"
The second profile is a different remix I figured I'd add as well by SavageRodent to allow use with a Magnet instead. Magnet is cylindrical 10mm diameter. Height of magnet isn't specific.