This is the the Small Rocket Lift Device (SRLD), developed by engineer Wendell F. Moore of Bell Aerosystems in the late 1950s. Unfortunately, the SRLD isn't in my garage ready for my commute but rather at the Smithsonian National Air and Space Museum.
Smithsonian magazine looks at the "Ill-Fated History of the Jet Pack":
It works by sending pressurized hydrogen peroxide through a decomposition catalyst—in this case a series of fine-meshed screens made of silver. The peroxide instantly expands into superheated steam, producing a few hundred pounds of thrust at the exhaust nozzles. These are controlled by the pilot’s hand grips. There’s no aerodynamic lift; the thing stays aloft through the physics of brute force. It has the glide angle of an Acme anvil.
By 1962 the Bell team had a patent, and a flying rocket belt. It flew in trials, in the Pentagon courtyard, in front of President Kennedy. But as soon as you took off, you had to find a place to land. And rocket belts are hard to build, maintain and control, expensive to fuel and relatively dangerous. As a practical matter, they’re a failure.
"The Ill-Fated History of the Jet Pack" (Smithsonian)
Bell Aerosystems rocket belt pilot Bill Suitor's helmet: