Airmar xSonic M135M Medium Chirp 1 kW In‑Hull Transducer - 9-Pin [M135C-M-9N]xSonic M135M Medium Chirp 1 kW In Hull Transducer 9 Pin The M135Ms medium frequency delivers the right combination of coverage under the boat, an extended depth range, and the ability to produce clean and accurate target and structure returns in mid to deeper water. Medium frequency also delivers excellent shallow to mid depth performance, bottom detail, and fish target separation. Operating at a frequency range of 85 to 135 kHz, this transducer