Sturdy & Durable: The round base & rectangular plate made of 6061-T6 aluminum alloy material with CNC machining and III grade hard anodized surface. The medium arm double socket arm made of powder-coated, 6061-T6 aluminum alloy for durability and reliability in the most demanding marine environments Solid Heavy-Duty: The 2.25" ball large fish finder mount consists of a d size 8.44" length double socket arm, a 5.04" x 2" marine electronic mounting plate and a 3.7" diameter round base Marine Electronic Mounting Plate: The rectangular plate consists of a D size 2.25" anti-slip TPU ball connected to a 5.04" x 2" rectangular plate. The plate includes 16 pre-drilled holes for compatibility with a wide range of marine electronic devices and mounts, including fish finder and gps chartplotter. In some applications, You can also drill additional holes to properly fit your electronics Round Base: The round Base consists of a D size 2.25" anti-slip TPU ball connected to a 3.7" diameter round plate. Including a variety of pre-drilled holes with industry standard AMPS hole patterns Medium Arm: The 2.25" ball double socket arm (medium arm) with an overall length of 8.44". Compatible with RAM Mounts & VAZESWIN D size 2.25" Ball components Compatible with Garmin fish finders and GPS chartplotters: ECHOMAP Plus 72cv 73cv, 74cv, 75cv 77cv; GPSMAP 722, 722xs, 742, 742xs; Striker Plus 5cv, 7cv, 7sv Compatible with Lowrance fish finders and GPS chartplotters: HDS Carbon 7, HDS LIVE 7, Hook Reveal 7 Series, Hook Reveal 9 Series Partial Compatibility: Compatible with Humminbird & Raymarine Partial Fish Finders, GPS Chartplotters. (Please Note: Not compatible with the Humminbird Helix 5, Helix 7, Helix 9, Helix 10, Helix 12, Helix 15 and Solix 10) Note: The package does not include installation screws and other hardware Made of powder-coated, aluminum alloy for durability an reliability in the most challenging environments