As a dome radar (rather than an open-array radar), the GMR 18 HD3 trades some raw resolution for a much smaller, lighter, self-contained package that mounts easily on a radar arch or mast without the swinging arm and larger footprint an open-array antenna needs — a common choice on mid-size sport-fishing and cruising boats where deck and mast space is limited. It draws around 15W in standby and roughly 40W when actively transmitting, running off 11-32V DC, and includes MARPA target tracking (which calculates a tracked target's course and speed automatically), dynamic auto gain and sea-clutter filtering, dual-radar support for boats running two radars simultaneously, and a notably quiet dome-drive motor compared with older radar generations — all aimed at giving a boater clear situational awareness in poor visibility, fog or night navigation without constant manual tuning.