A man entered the store at 1127 Industrial Road at about 7:45 p.m., took merchandise on display and headed toward a back door.
When an employee confronted him, he allegedly pulled out a handgun and then exited out the back door with the stolen items.
The suspect was described as a black man with a mustache and goatee, about 30 years old, 5 feet 9 inches tall with a medium build and a gold cap on one of his teeth.
He was wearing a black leather jacket, a gray hoodie, faded black pants and a black beanie.
Anyone with information about the robbery is asked to call the San Carlos Police Department at (650) 802-4277.
