Bar Nut Sprocket Cover For Sthil Chainsaws Pack Of 6 Replacement Bar Nuts For 14 Inch And 20 Inch Bars Fits MS170 MS180 MS240 MS260 MS270 MS280 MS290 MS310 MS390 MS360 MS360C MS440 MS460 MS640 MS650 MS660 Heavy Duty Pro Grade Metal Construction | dialed