Check the listing for details. RAM-B-103U RAM Double Socket Arm with Round Plate - B Si.... Color: Black, Condition: New. Listed at 36.44 USD. RAM Double Socket Arm with Round Plate - B Si... RAM-B-103U Genuine RAM Products! The RAM-B-103U consists of a 2.5 INCHES round base and double socket arm that will accept 1 INCHES ball bases. The round base contains pre-drilled holes, including the universal AMPS hole pattern. Designed into the mount is a 1 INCHES diameter patented rubber ball and socket system with adjustment points at both ends of the socket arm; this with a twist of the arm knob allows for you to maneuver the mount to your optimum viewing position.socket to socket length 3 INCHES hole pattern 4-Hole AMPS: 1.181 INCHES x 1.496 INCHES 3-Hole 120-Degree: 1.812 INCHES Diameterball size B Size (1 INCHES )weight capacity Standard Use: 2 lbsHeavy-Duty Use: 1 lbmaterials Marine-grade aluminumpackaging type Poly BagWeight 0.43 lb socket to socket length 3 INCHES hole pattern 4-Hole AMPS: 1.181 INCHES x 1.496 INCHES 3-Hole 120-Degree: 1.812 INCHES Diameter ball size B Size (1 INCHES ) weight capacity Standard Use: 2 lbsHeavy-Duty Use: 1 lb materials Marine-grade aluminum packaging type Poly Bag Weight 0.43 lb