The size of the NWSpinner is 3.75"

From the center of the string to the edge of the spinner the NWSpinner is 3.75". In all three cases Bearpaw, Beiter and Emerald II the bobbins are 3.25" from the center of the string to the widest point of the bobbin. This point happens to be the tension knob on all three Bobbins. So the Spinner is only 1/2" larger than the largest point of the bobbin. I have a lot of people ask me how tall do their posts on their stretcher need to be in order to use the NWSpinner the answer is about 4" minimum this give you a 1/4" clearance.