E-4 Complete Engine Pencil Anode - Zinc - 3/4" Brass Plug

Engine anodes thread into the end of a modified brass pipe plug which, in turn, threads into a port in the engine block or heat exchanger, thus placing the anode within the cooling water channels in the block where it helps protect internal engine components from corrosion.

• Pipe plugs made from high quality brass
• Built to military specification MIL-A-18001
• Made in California, USA

Note: In spite of Fisheries' promotion of aluminum sacrificial anodes as a generally superior choice of material, pencil anodes is an application where zinc is the anode material of choice. This is because aluminum pencil anodes are known to break at the neck and end up blocking coolant channels. As a result, most engine manufacturers - Cummins, Yanmar, Caterpillar, etc. - still use zinc for pencil anodes, and you should too. In fact, Fisheries does not stock aluminum pencil andes for the above reason.