Garmin GT15M-THF Thru-Hull CHIRP Transducer, 85-165 kHz, 600W, Stainless Steel, 8-Pin

Overview

The Garmin GT15M-THF is a stainless steel thru-hull transducer for mid-band CHIRP traditional sonar, built for a flush install that keeps drag low and keeps the sonar beam properly oriented.

It runs in the 85 to 165 kHz range and is intended to show clear fish arches, structure, and bottom contours. Depth performance is listed to 1,200 ft in saltwater and 1,900 ft in freshwater, depending on conditions.

This model is offered in tilt-angle versions so the element can sit closer to level once installed, which matters on boats with noticeable hull deadrise.

Key features

• Mid-band CHIRP frequency range: 85 to 165 kHz
• Depth performance listed to 1,200 ft in saltwater and 1,900 ft in freshwater
• Stainless steel thru-hull housing with a flush-mounted profile to reduce drag
• Clear target separation for fish arches, structure, and bottom tracking
• Uses transducer auto-identification for straightforward setup on compatible Garmin displays
• Available in multiple tilt angles to match common hull deadrise ranges

Variants

This transducer is offered in multiple tilt-angle configurations. The tilt angle changes how the element sits in the hull so the sonar beam points more straight down after installation.

The main difference between variants is the supported hull deadrise range. Match the tilt to your boat’s deadrise at the intended mounting location for cleaner returns and better bottom tracking.

• 010-02868-00: 0 degree tilt. Intended for hull deadrise angles from 0 to 7 degrees, where a level element is already close to true.
• 010-02868-01: 12 degree tilt. Intended for hull deadrise angles from 8 to 15 degrees, helping correct beam angle on moderate V hulls.
• 010-02868-02: 20 degree tilt. Intended for hull deadrise angles from 16 to 20 degrees, helping keep the beam closer to vertical on deeper V hulls.

Installation and setup

This is a thru-hull installation, so plan for a clear spot with access on the inside of the hull to tighten the hardware and route the cable. The best results come from mounting in clean water flow, away from strakes, steps, and through-hull fittings that can aerate the water.

Before cutting the hole, measure deadrise where the transducer will sit and match it to the tilt option. After bedding and tightening, confirm the face sits correctly and that the cable is supported so it is not taking vibration loads.

Compatibility and fit

This model is meant for compatible Garmin sonar displays that support transducer auto-identification and mid-band CHIRP traditional sonar. If you are replacing an existing transducer, confirm you have the right connector type and that the sonar channel supports the 85 to 165 kHz range.

A flush thru-hull transducer is a good match for boats that spend time at speed and owners who want consistent bottom tracking without a transom-mount hanging in the flow.

Use cases on board

This is a practical pick for anglers who run nearshore and offshore and want a mid-band view that balances coverage with detail, and for cruising boats that need dependable depth reading while underway. It also suits owners who prefer a clean hull profile over external brackets.

Maintenance and care

Keep the face clean for the best performance. In saltwater, rinse after use when possible and check periodically for marine growth, especially if the boat stays in the water.

As part of routine haul-out checks, inspect the housing for impact marks and confirm the bedding area and hardware remain secure.

Orders are processed within 2 business days, which includes verification, packing, and dispatch. Orders of $100 or more qualify for free shipping when eligible. For orders under $100, shipping costs are calculated at checkout based on destination, package weight, and selected service. International shipping is available for eligible products, and certain items may require additional handling, warehouse transfers, or may ship directly from the manufacturer, which can affect processing time.

Deliveries are handled by preferred carriers such as USPS, UPS, FedEx, DHL, and others depending on your location and selected service. Estimated delivery times are displayed at checkout and may vary due to customs processing, carrier delays, weather, postal disruptions, or other circumstances beyond our control. Once your order ships, you'll receive a confirmation email with tracking information. Tracking may take up to 24 hours to update on the carrier's website and is also available through your account when applicable.

We ship throughout the United States and to most international destinations for products eligible for international shipping. International orders may be subject to customs duties, taxes, brokerage charges, or other import fees, which are the customer's responsibility and are not included in the product or shipping price. PO Boxes are accepted only when shipping through USPS, and not all packages qualify for this option. If your order does not arrive within the estimated delivery window, please contact us at info@apollolighting.com or +1 (954) 375-0100 so we can assist with locating your package.

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Returns may be requested within 30 days of receiving your order. Items must be unused, uninstalled, unaltered, and returned in their original packaging with all tags, packing materials, blank warranty cards, manuals, instructions, accessories, and included items. Certain products, including installed or used electronics, electrical components, lighting, consumables, custom or special-order items, cut-to-length products, safety equipment, and merchandise exposed to water or marine conditions, may not be eligible for return.

To request a return, sign in to your account and select the applicable order and items, and submit your request for review. Eligible unfulfilled items may also be submitted for cancellation within 1 hour of placing the order. Returns or cancellations are not considered approved until you receive confirmation from Apollo Lighting. Please do not ship or drop off merchandise before receiving return approval and instructions.

Customers are responsible for arranging and paying for return shipping unless the return is due to an error by Apollo Lighting or the item is verified as defective, damaged, or incorrect. Missing, damaged, defective, or incorrect items must be reported within 2 business days of delivery, and photos or other documentation may be required for review. If the issue is verified, Apollo Lighting may provide or reimburse return shipping and issue a replacement or refund depending on the circumstances. International customers are responsible for return shipping, duties, taxes, customs charges, brokerage fees, and other costs associated with an international return.

After your return is received and inspected, approved refunds are issued to the original payment method and may take 5-7 business days to appear after processing. Original shipping and handling charges are nonrefundable, and the value of any included free items that are not returned may be deducted from the refund. Apollo Lighting does not charge a standard restocking fee on eligible returns. Returns that are incomplete, damaged, installed, used, altered, improperly packaged, or otherwise do not meet the eligibility requirements may be refused. We recommend using a trackable and appropriately insured shipping service for all customer-arranged returns.

For assistance, contact info@apollolighting.com or call +1 (954) 375-0100.

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Many products sold by Apollo Lighting include a manufacturer's warranty covering defects in materials or workmanship. Warranty terms vary by brand, product category, and model, so eligibility, coverage duration, exclusions, and available remedies are determined by the applicable manufacturer. We recommend reviewing the warranty information provided with your product before installation or use, especially for marine electronics, navigation equipment, lighting, electrical systems, pumps, safety equipment, and other specialized marine products.

If you need warranty service, the claim must follow the process established by the manufacturer, authorized service center, or designated warranty provider. You may be asked for proof of purchase, a serial number, product registration, photos, maintenance or installation records, or other documentation. Apollo Lighting does not determine or modify a manufacturer's warranty coverage or final claim decision, but we are happy to help provide purchase information and direct you to the appropriate manufacturer or warranty resource.

Keep your receipt, product documentation, serial number information, and original packaging when practical. Damage caused by normal wear, misuse, improper installation, insufficient maintenance, corrosion, impact, unauthorized modifications, electrical issues, or operation outside the manufacturer's specifications may not be covered. Warranty claims are separate from standard returns, so a product that has been installed, used, or exposed to marine conditions may no longer qualify for return while still remaining eligible for evaluation under the manufacturer's applicable warranty.

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