The RB-24E low water cut-off offers several features: Brass threads provide a metal-to-metal seal that ensures a leak-free installation.Integrated wrench flats enable secure installation without damage to the housing.McDonnell & Miller’s patented self-cleaning probe minimizes scale build-up and extends the recommended cleaning interval to 5 years.“Plug & Play” wiring harnesses are available for most residential gas-burning boilers.McDonnell & Miller RB-24E Low Water Cut-Off Patented...