Arm | Double Ball | 17mm to 1"/25mm
It works just as good as the original Garmin ball mount.
I ordered 3 TackForm Mounts to use with wireless phone chargers that I purchased separately. When I received the chargers, I realized the mounting ball was a different size. I called TackForm and they were able to help me solve the problem over the phone and had the extra ball mounts shipped to me within 3 days. I will use them again for all my mobile mounting solutions.
Product well made and worked perfectly