Dual Purpose Mount Plate: 2 mount plates include rectangle plate & round plate with TPU ball and contains a variety of pre-drilled holes that are compatible with several marine electronic devices, including fish finders,chartplotters,depth finders,the AMPS hole pattern is designed to install directly in a boat, kayak or on any flat surface Sturdy & Durable: This fish finder mount is made of aluminum alloy material, high strength and durable, which is corrosion resistant and can be used for a very long time, it remains strong and durable even under the impact of waves 360° Rotation: Dual 360° rotation ball mount are both the mount and the bracket 360 degrees rotated, the sturdy bracket with base is 5.4" tall, which provides a best view to meet your needs for fish finding. The Diameter of the base is 2.4", bigger and heavy-duty design for strong stability Easy to Install:The base and bracket can be disassembled separately, you can install the base on the boat first, install the bracket on the base after you fix the fish finder on the flat bracket. Loosening the switch on the side of the fish finder bracket, adjust the 2 ball swivel joints to meet your desired angle, and then tighten the switch Ideal for use as marine electronic device mounts for mounting fish finders, GPS chartplotters, depth finders, navigation, radios, etc. Compatible with Garmin, Lowrance, Humminbird & Raymarine fish finders and GPS chartplotters Important Note: Not compatible with the Lowrance Hook Reveal 5, Humminbird Helix 5/7/8/9/10/12/15 and Solix 10.Please confirm your device model before purchase !!!Please Note: Not compatible with the Humminbird Helix 5, Helix 7, Helix 8, Helix 9, Helix 10, Helix 12, Helix 15, Solix 10 and Lowrance Hook Reveal 5