Garmin GT21-TH S/S Thru-Hull ClearVü & CHIRP, 600W 50/200kHz Traditional, 500W 260 & 455 ClearVü CHIRP

The Garmin GT21-TH S/S Thru-Hull ClearVü & CHIRP transducer represents a serious upgrade for anglers and boaters who demand dual-frequency imaging with exceptional clarity in freshwater and saltwater environments. This stainless steel thru-hull unit combines traditional CHIRP sonar with advanced ClearVü technology, giving you the flexibility to switch between frequency ranges depending on water conditions, bottom composition, and target depth. Whether you're chasing structure in a northern lake or exploring deeper offshore channels, this transducer delivers the imaging tools professional anglers rely on to locate fish and navigate confidently.

The Garmin GT21-TH features a multi-frequency architecture: 600 watts of power at 50/200 kHz for traditional CHIRP sonar, and 500 watts across dual ClearVü frequencies at 260 and 455 kHz for high-definition side-imaging and down-imaging. This frequency diversity allows you to toggle between long-range coverage (50 kHz for deep water) and detailed structure resolution (200 kHz for shallow structure and precise target identification). The stainless steel housing ensures corrosion resistance in salt environments, while the thru-hull mounting design minimizes turbulence and dead zones—critical for maintaining signal integrity at cruise speeds or during active fishing. ClearVü imaging produces sharp, photograph-like views of the water column and bottom, making it easier to distinguish baitfish, vegetation, and hard structures.

This transducer is ideal for boaters with Garmin fishfinder and chartplotter systems that support GT21 compatibility, including legacy and current GPSMAP and Echomap units. Professional anglers and tournament competitors benefit from the fast frequency switching and superior sonar resolution when targeting bass, walleye, pike, or saltwater species where precision matters. Installation requires a thru-hull mounting location below the waterline with proper sealant and backing plate; consult your vessel's hull material and Garmin installation guidelines to ensure optimal performance. The transducer's rugged construction and proven reliability make it a trusted choice for both recreational and commercial fishing operations.