Millions of years ago in the Gold Digger Universe, there existed a race of intelligent Saurians (Dinosaurs) on Earth with an advanced civilization. Their technology was based on being able to operate/exist in two phases of reality at the same time. Penny Pincer who discovered the City of Civ-Alpha 4 miles below the Nevada desert had been working with and reverse engineering the tech for modern day use with the help of Gina Diggers.
A Giga Key was found by Charlotte Pincer in a cavern under the coastal region of Kuwait while she was trying to hide from the Regional Emir General Akbar.
In preventing the death of Penny and Ace, Charlotte caused a massive explosion that caused a cave in that buried the Giga Key under tons of Sand and rock. Fortunatly she had scanned the device for Penny from the correct angles to allow Penny to reverse engineer the Giga Key and create another one.
A Giga key is a Beta key of immense size with the singular purpose of being "a dongle for interfacing with a Beta Engine control system."
it can activate Beta devices with the level of power to move solar systems, and exactly what is needed to pry open a hole between the Gold digger main universe and Quasi space where Brittany is trapped.
1. Automatically locate other sources of Beta technology, ( it will just up and go when energized.)
2. To date it has formed portals in space from one point to another for rapid transit, covering Thousands of miles in a matter of seconds by moving into Beta Phase. (Unlike a normal beta key that could turn on a device for that purpose but couldn't transit that way on it's own.)
3. Act as an ignition key for a Beta Engine of immense size (example the engine it found on it's first field test was powering a machine 800 feet tall and over 150 thousand tons in Alpha phase alone!)
It was used for the initial test on site to jump-start the beta engine in Gigliathon - the 800 foot machine listed earlier - to open a test portal into quasi space but was presumably TAKEN by Dreadwing in the resulting confusion of an explosion that catapulted Gina into Quasi-space.