Rule-A-Matic® Float Switch w/ Fuse Holder Year after year, the Rule-A-Matic has been the switch of choice for boaters the world over. Our latest design now includes a removable base for easy cleaning and servicing, a mercury free snap switch tested to over one million cycles and marine grade blocked wire. Designed for pumps drawing up to 14 Amps. Now includes a 2 year warranty.