Blue Sea 1811 VSM 422 Tank Sender Gasoline Tank Level [1811]1811 Features: Accurate used with the Vessel Systems Monitor VSM 422 PN 1800 can be precisely calibrated for each tank* Reliable SSI Technologies, Inc. Fluid Trac is non contacting eliminating any mechanical moving parts that can wear and cause intermittent or complete signal loss Digital filtering Eliminates errors due to liquids sloshing in mobile tanks * Calibrated for use with Blue Sea Systems Vessel Systems Monitor VSM 422 only WARNING: This