The Cosmic Rod sometimes called Cosmic Staff was invented by Ted Knight, and based on the earlier Gravity Rod.
The Cosmic Rod gives the user the ability of flight and the conversion of stellar energy into powerful blast emission as well as afforded trans-dimensional travel. Different variations have allowed alternate abilities including; levitating objects, creating force fields for both offense and defense, manipulating energy, and creating simple energy constructs. Further modifications to the rod gives it magnetic and gravimetric manipulatory abilities The rod also will "attune its self" to the user allowing the user to control the rod by thought and make it difficult for others unregistered to wield it.
Ted Knight invented the Cosmic Rod and used it to fight crime as the first Starman. It was a small handheld rod. A prototype from the next starman cosmic rod was dubbed Gravity rod.
Jack Knight uses the Cosmic Rod throughout his career as Starman. The rod is a long staff. When he retires from superheroing he gives the rod to Courtney Whitmore, the Star-Spangled Kid, who changes her name to Stargirl to respect the legacy of Starman.
Farris Knight, the DC One Million Starman and descendant of Ted Knight and Mist, used a small handheld device called the Quarvat.