![K157fmi oil filter o-ring](http://rbmcstore.com/cdn/shop/products/o-ringfork157fmioilfilter_{width}x.jpg?v=1597842181)
small o-ring to fit in front of the oil filter before you fit the filter, this o-ring goes between the engine and oil filter just before installing the oil filter.
- inside diameter 13mm
- outside diameter 16.5mm
- thickness 1.75mm
for all K157FMI engines