The RAM-D-115-C-KNOB9H consists of a base with a 2.25� diameter D size ball, a short arm, a Hi-Torq� wrench and a 6.25� x 2� marine electronic plate with a D size ball for supporting larger devices. This marine electronic plate contains different combinations of pre-drilled holes and is a direct fit for 9�-12� fishfinder gimbal brackets. For cold weather environments, the included Hi-Torq wrench helps to tighten the knob on the arm for a secure hold. Supports devices such as the Lowrance HDS-9 Gen2 Touch, Garmin GPSMAP 7407 and more. Overall Length: 7.325" Weight Capacity: Up to 10 lbs. The 6.25" x 2" rectangle base is a universal mounting bracket with a selection of mounting hole locations. In certain applications additional holes may need to be drilled for proper fit with your electronic device.