Echonautics BT87H1KW-18 1kW 130-210kHz High CHIRP 18d Tilted Element Bronze THEchonautics BT87H1KW 130 210kHz 1kW High CHIRP 18 Tilted Element Model: BT87H1KW 18 Superior shallow water performance and bottom detail The Echonautics BT87H1kW is a low profile thru hull CHIRP transducer designed to minimize drag and to perform at high speeds. Thanks to the narrow beamwidth, it is excellent for pinpointing fish holding tight to reefs, wrecks, and other structures. Specifications Function Depth and Temperature Frequency CHIRP 130 210