Double Socket Short Arm for 1 inch Ball The RAM-B-201-A, short double socket arm, has a socket at both ends that accommodates 1 inch ball bases. This socket technology allows for almost infinite adjustment and perfect viewing angles. Dimensions: Overall Length: 2.38 inch Socket-To-Socket Length: 1.75 inch Material: Powder Coated Marine Grade Aluminium Ball Size: 1 inch Rubber Ball inch B inch Size Note: For security purposes a locking knob is available for this arm, part number RAM-KNOB3L