The MTD Trimmer Clutch Drum Assembly Kit is used on gas trimmers and tillers. This trimmer clutch drum kit includes: Clutch Drum, Clutch, Clutch Washer and the Screw which has a left-handed thread. A centrifugal clutch is a part that uses centrifugal force to connect two concentric shafts, with the driving shaft nested inside the driven shaft. Today's centrifugal clutches will function even when they shouldn't, far beyond the point of when they need to be replaced. Keeping an eye on equipment performance will determine when the centrifugal clutch requires attention, which is why you need this clutch assembly kit on hand. This trimmer clutch drum kit is perfect for residential use. Get the job done right with this trimmer clutch drum kit!