<http://schema.org/description>
"Single Dome Control Knob We offer high quality metal dome control knobs for smooth shafts.These knobs with dot marking are perfectly matched to our preamps.6mm inner diameter, 18mm overall diameter, and 18mm height."^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.bestbassgear.com/noll-single-dome-knob.htm>