This is the better quality Aftermarket ma660 crankcase. We know there are cheaper ones to be found out there but oftentimes on those the quality is lacking. The cheaper ones tend to have thinner metal, holes that are untapped or improperly tapped, and the dimensions do not line up to spec. We've been using these crankcases for years with great success. Not all aftermarket parts are created equally and this is certainly the case (no pun intended) here
Parts Name: Crankcase
Fits: STHL MS660 066 Chainsaw
Replace OEM: 1122 020 2116