The easy clamping and releasing feature of these clamping levers is what makes them perfect for this application. A flick of the fingers allows the user to unclamp the brackets and adjust the harmonica's position to the perfect level. In contrast to a clamping operation utilizing threads, these levers permit torque-free clamping. The lever has been designed to insure that its movement cannot exceed the maximum clamping position.
You can see more clearly in this diagram where the pair of GN 927's are employed in the "harp-rack."
GN 927 levers are RoHS compliant, with zinc die cast handles and a matte black plastic coated, abrasion-proof epoxy resin finish. Components are zinc plated, blue passivated steel. They are available with two types of technopolymer contact plates: a fixed version, or an adjustable contact plate, with which the distance between the eccentrical cam and the contact surface is adjustable by means of a fine threaded knurled nut.
If you're interested in purchasing the harmonica holder itself, complete information is available from the manufacturer on their website.
We appreciate that a component we offer is helping people make beautiful music!