Garmin GT51M-THPGarmin GT51M THP Perfect for the coastal and offshore fisherman who want CHIRP traditional sonar, CHIRP ClearV and CHIRP SideV scanning sonar with stainless steel stems, this pair of thru hull mounted transducers consistently displays clear and crisp fish arches with superior target separation as well as clear pictures of objects, structure and fish that pass below and to each side of your boat and is optimized for rough sea conditions. The CHIRP