The RAM-B-202-G2 consists of a 1" diameter rubber ball connected to a flat 2.5" diameter base. This mount has a three hole pattern which will connect to the base of the Garmin Marine GPS unit swivel mounts. Included is a hardware pack for assembly for your Garmin Fishfinder.
Hardware Included
(3) #6-32 x 3/8" Machine Screws
(3) #6-32 Nut Inserts
Hole Pattern
4-Hole AMPS: 1.181" x 1.496"
3-Hole 120-Degree: 1.812" Diameter