Autolite Copper Spark Plug 254 for Select Chainsaws, Trimmer, Weed Eaters, and Engine Power Equipment: The Autolite Small Engine Spark Plug, 254 replaces the following spark plugs: Champion (CJ6, CJ4, CJ8, RCJ4, RCJ6, RCJ8): NGK (BM6A, BM6Y, BM7A, BM7Y, BMR6A, BMR7A) Fits select models of these popular applications. Check your owner's manual for the spark plug to replace. Chainsaws: Homelite, Craftsman, Poulan, Wards, Remington, Pioneer, Lombard, McCulloch, Echo, Lancaster, Partner, Tanaka. Engine power equipment: Tecumseh, Mitsubishi, Kawasaki, Subaru Robin, Kioritz. Trimmers/weed eaters: Green Maching, Echo, Robin, John Deere, Makita. Tillers: Hoffco. Outboard motors: Tanaka, Aquabug, Clinton, Chief, McCulloch. Copper-glass seal bonds insulator, terminal post center electrode together; assures full required voltage at spark gap; gas-tight seal (100% leak proof). Multi-rib insulator reduces danger of "flash-over". One-piece terminal post adds strength to spark plug. Resistor reduces radio frequency interference (RFI) and electrode erosion. Cold-formed steel shell precision rolled threads Full copper core electrode provides better performance in all conditions Autolite highly recommends that you consult with your equipment's repair manual for specific instructions for changing the spark plug.