It replaces the bootchip (usually GKB00036) on a 044 flash card and has a few built in utilities that are accessible by pushing the MPU selftest button and turning on the power. A menu appears that allows you to key the machine, clear RAM, clear EEPROM, and a couple of other things that appear to require an external server. What I really like the most is being able to turn off the SHA and DSA checks on startup. With those off my Superstar board boots up in about 18 seconds, compared to over 2.5 minutes with the checks on. Being able to key the machine without swapping out the bootchip is also really nice. Basically it's a built-in keychip with the ability to bypass checks allowing much faster startup.
Note that it is not my auction.