In-hull transducers attach to the interior floor of the hull without drilling any holes. In-hull transducers work with solid fiberglass hulls and are not recommended for metal, wood, or cored fiberglass hulls.

In general, your in-hull transducer must be mounted over a part of the hull that is in constant contact with smooth water. Sending the sonar signal through the hull can reduce the transducer's depth capability, so mounting it over the smoothest water helps optimize the transducer's performance. Garmin^® offers in-hull models that are optimized for higher speeds and greater depths and for hull deadrise angles of 0 to 25 degrees (Deadrise Angle).