The RAM-201U-BL, standard double socket arm with small size locking knob, has a socket at both ends that
accommodates 1.5" ball bases. A single spring inside the arm opens the end sockets, allowing you to pivot
the ball and socket connection. This socket technology allows for almost infinite adjustment and perfect
viewing angles. The locking knob, includes a brass 1/4"-20 thread; this allowing you to disengage the
screwing of the knob. Once you have set your mount in the location you need, you can lock it in place and
feel safe that your mounted device will stay right where you left it.