The manfrotto mvr901ecla remote control is used with lanc canonsony cameras and can be clamped onto round tubes with a 12 23mm diameter such as a tripod or video head with handle to allow control of the cameras settings without dealing with the buttons on the camera itself the mvr901ecla features a stand by push button recstop push button zoom and focus direction knob by software multi speed zoom and focus knob focuszoom knob max speed zoom potentiometer rec zoom and focus indi