Rule Industries Float Switches

Rule Industries Float Switches: The Industry Standard for Marine Bilge Control

When it comes to keeping your vessel dry and safe, few components are more critical than a reliable float switch. Rule Industries has been setting the bar for marine float switches since 1965, and their products remain the benchmark against which all others are measured. As part of the Xylem family of water technology brands, Rule brings decades of engineering expertise to every switch they produce — and nowhere is that more evident than in their lineup of float switches.

Why Rule Float Switches Stand Apart

Rule automatic float switches are recognized as the world's largest-selling marine float switches, a distinction earned through consistent performance in the harshest on-water conditions. Every switch in the Rule lineup is non-mercury, making them an environmentally responsible choice without sacrificing reliability. They are ultrasonically welded and sealed for a watertight construction, and have been tested to over one million cycles — a testament to the durability boaters demand when lives and vessels are on the line. All models are ignition-protected, a critical safety feature in fuel-carrying marine environments, and feature no exposed metal to corrode.

Wiring is a key detail that Rule gets right: the marine-grade, abrasion-resistant wire exits from the top of the switch housing, keeping connections high and dry even when the bilge floods. Multiple models are available to accommodate various bilge pump amperage loads, giving boaters the flexibility to match the switch precisely to their pump system.

Rule Float Switch Product Lines

Rule-A-Matic: The original Rule-A-Matic has long been the industry standard mercury-free float switch for the marine world. Its latest iteration features a removable base for easy cleaning and servicing, along with a mercury-free snap-action mechanism. It is rated for use with pumps drawing up to 14 amps and operates on 12–24V DC.

Rule-A-Matic Plus: A compact, sleek evolution of the classic Rule-A-Matic, the Plus model features a fully integrated, impact-resistant cover designed to keep out debris and prevent jamming — one of the most common failure points in bilge float switches. It includes dual-level anti-clog water slots, a built-in manual test lever so you can periodically verify operation without flooding the bilge, and is compatible with pumps drawing up to 20 amps across 12V, 24V, and 32V DC systems.

Rule SuperSwitch: Designed for the toughest applications, the SuperSwitch is Rule's heavy-duty offering for demanding commercial and recreational use. This non-mercury switch activates the pump when water reaches 2 inches and shuts it off when levels drop to 3/4 inch, keeping bilge water well under control. It also supports pump loads up to 20 amps and includes the same highly abrasion-resistant, marine-grade 14-gauge blocked wiring found across the Rule lineup.

Choosing the Right Rule Float Switch

Selecting a Rule float switch comes down to a few key considerations: the amperage draw of your bilge pump, the available space in your bilge compartment, and the severity of the conditions your vessel typically faces. For most recreational boaters running standard pumps, the Rule-A-Matic or Rule-A-Matic Plus offers an ideal blend of compact design and proven reliability. Those with larger vessels, commercial applications, or demanding environments will appreciate the SuperSwitch's robust construction and precise activation thresholds.

Whether you're outfitting a new build or replacing a worn-out switch on a trusted vessel, Rule Industries float switches deliver the kind of trouble-free, automatic bilge protection that lets you focus on the water ahead — not what's accumulating below deck.