This gearbox is designed to fit Stihl models including HT73, HT75, HT100, HT130, HT131, HT250, KM110, KM130, KM90, FS85. Note: Not compatible with 1/4" chains. Gear Head Pole Saw Gearbox Compatible with Stihl HT73 75 100 130 131 250, KM90 110 130, FS85, WT Spur Sprocket 3/8-6T Pruner Pole Saw Tree Cutter Replaces 4182 200 0070, 4138 205 0008.
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