FURUNO FCV-588 8.4" Color LCD Fish Finder - New RezBoost™ technology provides incredible boost in resolution & target separation when using a compact narrowband transducer. Dual frequency fish detector equipped w/ zBoost signal processing technology. Configurable alarm function (depth, echoes of fish, etc.). Fast transfer speed of 3,000 PRR (Pulse Repitition Rate) per minute (at a depth of 5m)