{"product_id":"garmin-gt21-th-sonde-traversante-clearvu-chirp-500w-600w-temperature-8-pin","title":"GT21-TH Transducer - Through-hull ClearVü CHIRP and traditional sonar","description":"\u003cp\u003e\n    The Garmin GT21-TH is an 8-pin through-hull transducer designed to provide advanced underwater detection capabilities. This model combines two distinct sonar technologies: CHIRP ClearVü and traditional sonar. The CHIRP ClearVü operates at 500W on 260\/455kHz frequencies, delivering near-photographic images of structures and fish beneath the vessel. In addition, the traditional sonar delivers 600W on 50\/200kHz frequencies, ideal for deep detection and target separation. A temperature sensor is also integrated, providing critical environmental data for fishing conditions analysis.\n\u003c\/p\u003e\n\u003ch3\u003eOptimal installation and performance\u003c\/h3\u003e\n\u003cp\u003e\n    The through-hull design of the GT21-TH transducer ensures operation in non-turbulent waters, essential for optimal sonar performance. Installation requires careful attention to hull deadrise angle. If the deadrise angle exceeds 5°, the use of a fairing block is recommended to align the transducer parallel to the waterline, maximizing sonar accuracy. Anti-rotation bolts are included and must be installed to prevent device rotation during movement, avoiding potential damage to the boat. Garmin emphasizes updating your chartplotter software after installation to ensure compatibility and best performance.\n\u003c\/p\u003e\n\u003ch3\u003eCompatibility and technical requirements\u003c\/h3\u003e\n\u003cp\u003e\n    The GT21-TH transducer installation is adaptable to various hull types, including fiberglass hulls (with or without core) and metal hulls, each requiring specific drilling and sealing procedures. Required tools range from a 3mm drill bit to a 32mm hole saw, including adjustable wrenches and high-quality marine sealant. Mounting location is critical: it must be ahead of propellers and turbulence generated by hull appendages. For keel boats, specific positions relative to the keel and centerline are recommended. The GT21-TH positions itself as a robust and performant solution for recreational boaters and anglers requiring detailed and reliable underwater mapping, though it is not the most powerful in Garmin’s CHIRP range, such as the GT51M-TH or GT56UHD-TM models, which offer higher frequencies and power for more specific applications. It represents an excellent balance between performance and cost for versatile use.\n\u003c\/p\u003e","brand":"Garmin","offers":[{"title":"Default Title","offer_id":55860280361300,"sku":"010-01962-10","price":435.38,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0988\/3274\/4788\/files\/main_5ff36a25-0fc8-45ce-a882-e8f3a0d9682d.jpg?v=1779191108","url":"https:\/\/skysat.fr\/en-us\/products\/garmin-gt21-th-through-hull-sonde-clearvu-chirp-500w-600w-temperature-8-pin","provider":"Skysat","version":"1.0","type":"link"}