OEM Stihl pre filter to fit stock air filter systems. please check list bellow for fitment
Small HD2 Pre Filter will fit the following saws running Air filter S0000 140 4407
044, 046, 064, 066, 084, 088
MS440, MS441, MS460, MS461, MS650, MS660, MS880, MS881
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Larger Pre Filter fitting Air Filter 1144 140 4402
Fits The following
MS500i & MS661