The K400C 3/8C has a unique design, in that it can be installed as a trunk lip mount as shown, or it can swivel and install vertically on a door jamb or hatchback. That, and the heavy duty construction make this a high quality mounting solution for most vehicles.
The top section of the bracket can tilt as well to help keep the antenna vertical on sloped surfaces. The coax cable and stud are removable and the coax can be switched to a left or right channel so the coax isn't facing an awkward direction after installed. This mount uses a 3/8x24 thread connection (like most CB antennas) and the coax cable is equipped with a removable PL-259 connection.