NGK CMR6H Spark Plug. Genuine NGK Spark Plug for Stihl MS171 Chainsaw - OEM No. Stihl BG56, BG66, BG86, SH56, SH86, BR200, BR500, BR550, BR600, FC56, FC70, FC90, FC95, FC100, FC110, FS40 (�10mm Plug engine only), FS50, FS70, FS56 (�10mm Plug engine only), FS87, FS90, FS100, FS110, FR130, FS130, FS310, FS460 C-EM, MS150 C-E, MS171, MS181, MS181 C, MS192 C-E, MS211, MS211 C, MS231, MS251, MS241 C-M, HT100, 101, 130, 131, KM56, KM90, 100, 110, 130, HL90, HL95, HL100, HS81 models, HS86 models, HS46 C-E, HS56 C-E, HT56, HT100, HT101, HT130, HT131, MS 201 T, MS 201 TC.
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