SNES Burn-In/Test Cartridge
This is the most commonly found of the different SNES test cartridges that are in circulation. It tests the the various SNES accessories: Controllers, the Super Scope, and the SNES Mouse. When the unit is powered on (depending on what accessory is in the first slot), a screen will appear that guides you through the testing process for that particular item.
There are four different revisions of this that have been found: A, B, C, D. A and B have different unique style labels, though C and D look like the one pictured above.