Rule-A-Matic® Float Switch w/Fuse Holder

The Rule-A-Matic® Float Switch with Fuse Holder is the industry standard for automatic bilge pump control on recreational and commercial vessels worldwide. After decades of proven performance, this float switch remains the go-to choice for boaters who demand reliability in the toughest marine environments. Whether you're running a center console, cruiser, or displacement hull, the Rule-A-Matic automates water removal—keeping your bilge dry and your boat safe without manual intervention or electrical complexity.

This switch operates on a simple mechanical principle: as water rises in your bilge, the sealed float rises with it, triggering a snap-action contact that activates your pump. The latest generation features a mercury-free snap switch engineered and tested to exceed one million operational cycles—eliminating environmental concerns while guaranteeing durability in salt spray, fresh water, and fuel-contaminated bilges. The removable base design allows quick cleaning and servicing without breaking electrical connections, a critical advantage when routine maintenance is necessary at the dock or during off-season storage.

The integrated fuse holder protects your pump circuit from electrical surges and shorts, reducing the risk of fire or equipment damage—essential insurance for any boat's electrical system. Installation is straightforward on most bilge configurations; the compact footprint (5 x 3 x 8 inches) fits standard sump housings and mounting brackets used across Rule and compatible pump systems. Experienced boaters and marine technicians trust the Rule-A-Matic because it works silently, requires no calibration, and performs identically whether you're on freshwater lakes or offshore in heavy seas.