RAM® Composite Ball Adapter with AMPS Plate
AMPs Base with 1" Ball, Plastic
The RAP-B-347U base consists of a 1" diameter rubber ball connected at right angles to a 2" x 1.7" square base. The base has four pre-drilled holes at each corner, making the universal 1.5 x 1.188 (hole spacing) AMPs hole pattern.  Mounting hardware not included.  Mounts to the back of many Garmin cradles, or can be mounted anywhere using screws or bolts. Weight: 0.8 oz (23 g)

SPECS:

Hole Pattern:
4-Hole AMPS: 1.181" x 1.496"

Ball Size:
B Size (1")

Weight Capacity:
Standard Use: 2 lbs
Heavy-Duty Use: 1 lb

Materials: 
High strength composite

Weight:
0.08 lb

Q&A

Q: What diameter are the holes?
A: The hole diameters are 3/16".