Super Fine! This 18.5 Micron 100's Merino Top is one of many varying microns we carry in Merino Wool. The lower the micron Number the finer the fiber. This Top is Silky smooth, you won't want to let it go! It has been superwash treated to reduce shrinkage when machine washed. This fiber will not felt. This Merino is from South Africa (Cape) or South America depending on availability and is from non-mulesed sheep. Perfect for hand spinning, dyeing, and other craft uses!