RAM Ball Adapter with Hardware for Garmin Fishfinders (RAM-202-G4U) (sku 54840)The RAM 202 G4U consists of a 1. 5" diameter rubber ball connected to a flat 2. 5" diameter base. This mount has pre drilled holes, including the universal AMPS hole pattern. Included are 3x (#8 32 x 5 8 PH PD Mach Screws) and 3x (#8 32 SS Nylock Nuts) that will connect the RAM 202 G4U to the bottom of the Garmin echo. HARDWARE INCLUDED (3) #8 32 x 5 8" Machine Screws (3) #8 32 Nylock Nuts HOLE PATTERN 4 Hole AMPS: 1. 181" x 1. 496" 3 Hole 120 Degree: