Garmin GMR™ 18 HD3 Radar Dome
Free returns on all eligible orders
You have 30 days to request a return. All sale items are final sale.
The Garmin GMR™ 18 HD3 is a compact 18" magnetron radar dome designed for boaters who want reliable, high-definition situational awareness without the bulk of an open-array system. With 4kW of transmit power and a 36-nautical-mile maximum range, it delivers a clear picture of surrounding traffic, landmasses, and weather — even in challenging conditions.
Key Features
- 4kW transmit power — strong returns at distance for confident navigation
- 36-nautical-mile maximum range — broad coverage for offshore and coastal passages
- 18" space-saving dome — fits easily on smaller vessels and T-tops
- MARPA target tracking — monitors up to 10 moving targets simultaneously
- Dynamic auto gain and sea clutter filter — automatically optimizes the picture in varying sea states
- Dual-radar support — run two radars simultaneously when paired with a compatible Garmin chartplotter
- Quiet dome drive motor — low-noise operation suitable for helm stations and flybridge installations
Compatible Bundles & Related Products
This radar is available as part of complete chartplotter/radar bundles:
- Garmin GPSMAP 1243xsv Chartplotter with GMR 18 HD3 Radar Bundle
- Garmin GPSMAP® 1243xsv GPS Chartplotter/Radar Pack with GMR 18 HD3 Radome
- Garmin GPSMAP® 943xsv GPS Chartplotter/Radar Pack with GMR™ 18 HD3 Radome
Need a dedicated power cable? See the Garmin Power Cable for GMR™ Radars, 48'.
Looking for a solid-state upgrade? Compare with the Garmin GMR Fantom 18x Solid-State Doppler Radar Dome.
Parts Desk Insights
Best use case: The GMR™ 18 HD3 is the go-to choice for powerboats and sailboats in the 25–45 ft range where mast or arch space is limited. It pairs directly with any Garmin GPSMAP or echoMAP chartplotter via a single cable, making it a straightforward first-radar installation or a replacement for an aging dome. Boaters running overnight passages or navigating busy commercial waterways will benefit most from the MARPA tracking and extended 36 nm range. If your vessel already has a Garmin MFD network, dual-radar mode lets you run this dome alongside a larger open-array for overlapping coverage zones.
Shipping information
In-stock and OEM parts: ship same or next business day.
Locally warehoused items: ship within 3–4 business days.
Special-order items: timeline confirmed after order.
Returns & warranty
Returns & Satisfaction Guarantee
We stand firmly behind the quality of every product we sell. Your confidence matters to us — and we back it with a straightforward 30-Day Satisfaction Guarantee.
If you are not fully satisfied, you may request a return within 30 days of delivery. All returns must receive pre-approval prior to being sent back. Unauthorized returns will not be accepted.
To qualify for a return:
Item must be in new, unused condition
Product must be in its original packaging
All parts, components, hardware, manuals, and accessories must be included
Packaging must be undamaged and suitable for resale
Important:
Electronics are strictly inspected. No returns on open-box electronics. Exceptions may apply only with prior written approval. Any electronic unit that has been installed, powered, activated, or altered may not be eligible for return.
We are serious about product integrity — and equally serious about taking care of our customers. If there is ever a product issue, contact us immediately so we can make it right.
For return authorization, please contact our support team before shipping anything back.