The RAM-D-201U-NK, double socket arm without knob, has a socket at both ends that accommodates 2.25" ball bases. A single spring inside the arm opens the end sockets, allowing you to pivot the ball...
The RAM-E-201U, double socket arm, has a socket at both ends that accommodates 3.38" ball bases. A single spring inside the arm opens the end sockets, allowing you to pivot the ball and socket...
The RAM-D-201U-MI1, standard size double socket arm with jam nut, has a socket at both ends that accommodates 2.25" ball bases. A single spring inside the arm opens the end sockets, allowing you to...