Airmar PM111 LHW 2kW CHIRP Pocket-Mount Transducer, No Connector

The PM111 LHW is the pocket-mount variant of Airmar's 2kW wide-beam CHIRP transducer family. The LHW designation stands for Low + High Wide, which calls out the defining feature of this element: the high-frequency band uses a constant 25-degree beamwidth across the entire 150-to-250 kHz frequency range rather than the narrow 4-to-8 degree beam most high-frequency transducers run. The wider beam gives you about twice the under-boat coverage at the high frequencies, which means you find more fish in the upper water column on a single pass over a stretch of water. For inshore work and for pelagic fishing where the targets are spread out at mid-depth, the wide-beam high element makes a meaningful difference compared to the narrow-beam alternatives. The PM (pocket-mount) housing is the right pick for boats where the transducer needs to sit recessed inside a fiberglass cavity rather than protruding outside the hull on a thru-hull stem.

The low-frequency element handles the deep-water side. The 2 kW low band CHIRPS from 38 to 75 kHz with a 19-degree port/starboard beam and a 10-degree fore-aft beam, narrowing to 10 and 5 degrees at the upper end of the band. Maximum depth on the low band runs to 6,000 feet (1,829 meters), which is plenty for canyon-edge work and most offshore deep-drop applications. The 1 kW high-wide band tops out at 500 feet (152 meters), which is the right depth range for what wide-beam high-frequency does best: fish-arch detection on inshore and shallow-water targets. Total usable bandwidth across both elements is 137 kHz, covering the popular 50, 68, and 200 kHz fishing frequencies plus everything in between. Modern CHIRP-capable sounder modules can sweep either band or both simultaneously based on what the operator wants to see.

The pocket-mount install style is what differentiates the PM111 from the R109 thru-hull variant. Rather than penetrating the hull with a stem, the PM111 sits inside a custom-built fiberglass cavity recessed into the hull, with the transducer face flush with the hull's outer surface. Solid fiberglass is the only compatible hull material since the pocket cavity is constructed during the install, and the cavity construction is what lets the PM111 handle any hull deadrise angle, unlike thru-hull alternatives that are limited by fairing geometry. The pocket-mount approach is what offshore commercial fishing operators and serious sportfish boats often prefer because there's no protrusion outside the hull, which means no drag at speed, no risk of striking debris, and no underwater stem to bed and seal long-term.

This SKU specifically is the no-connector variant. The cable ends in unterminated wire pigtails rather than a manufacturer-specific connector. That's the right pick when you're hardwiring directly to a sounder module's input terminals or routing through a junction box mid-cable. For chartplotters with specific connector requirements, the connector-equipped variants of the same element are alternative SKUs. The urethane potted housing handles long-term saltwater immersion without degradation, and the patented Xducer ID auto-detect technology lets compatible chartplotters automatically identify the transducer type and load the correct calibration tables without manual setup. The transducer element itself is 16 internal broadband ceramic assemblies, which is what gives the PM111 the bandwidth coverage and target resolution that the heavy commercial-grade transducers are known for.

The 30 pound (13.6 kg) weight requires structural hull integrity around the install point, which is standard on boats 40 feet and above. The pocket cavity construction is a specialist job: a marine electronics installer with pocket-mount transducer experience is the right person for the install, since the cavity dimensions, the fiberglass layup, the acoustic window, and the alignment all need to be done correctly. The cavity becomes a permanent part of the hull, so a survey-quality install is what determines long-term performance. We can recommend an installer in your area for the cavity work, and we can spec the right sounder module pairing for the transducer before you order. Warranty service for the PM111 LHW goes through Airmar's standard authorized network.

One more pattern worth knowing about choosing between the PM (pocket-mount) and R (thru-hull) versions of the same LHW element. The PM111 LHW is acoustically identical to the R109 LHW thru-hull variant. Same low element, same wide-beam high element, same power rating, same depth performance. The difference is purely how it mounts to the boat. The pocket-mount has no drag, no trailer-handling issues, and no protruding stem to damage, but requires solid fiberglass hull and a custom cavity that's part of the install. The thru-hull has the broadest hull material compatibility and is the simpler install on existing boats that didn't plan for a pocket cavity from the start. For new builds and for refits where the yard is doing serious hull work anyway, the pocket-mount is often the right pick. For retrofit work on boats where cutting and laying up a cavity is impractical, the thru-hull variant is the right pick. Same fish-finding performance either way.