RULE HIGH WATER BILGE ALARM Consists of a Rule 035A float switch and an in-dash gauge that features both a visual and an 85 db audible alarm . This unit allows an unmanned compartment to be constantly monitored. For additional compartments, add Model 35 float switch. Complies with CFR 182.530 which requires a visual and audible alarm in each unmanned space on commercial vessels at least 26 ft. (7.9m) in length.