Marine UL Listed with red function light. Remains ON & monitoring even when gas control Panel is OFF. Its sends an alarm signal to the Control Panel when an LP Gas is present at 10% Lower Explosion Limit (LEL) or more. Up to 2 additional Gas Detectors can be easily added to the systems (#1300-7760 and #1300-7761) with either the 10ft. or 20ft. Quick Connect Cable (#1300-7721-120 and 1300-7721-240 respectively) Each draws 163 M.A.