The Humminbird XI 9 1521 Chirp Ice Transducer brings Dual Spectrum CHIRP sonar to hardwater anglers who want a clear view of fish, their jig, and bottom structure beneath the hole. Its 15- and 21-degree beam angles operate across a 130-250 kHz frequency range, giving anglers focused 2D sonar coverage for working different depths and fishing situations. The 8-foot cable provides practical reach around portable electronics and ice shelters, making this transducer a useful choice for chasing walleye, perch, crappie, lake trout, and other winter species. Dual Spectrum CHIRP sonar 15Adeg and 21Adeg beam angles 130-250 kHz frequency range 8 ft cable for ice setups Compatible with HELIX CHIRP units that features Ice Fishing mode, except for HELIX 12 CHIRP SI GPS, HELIX 12 CHIRP DI GPS, HELIX 12 CHIRP GPS Manufacturer's one-year limited warranty