As a member of the Philadelphia Pops for thirty years I have never seen such a beautiful shelf and mute holder as the one designed and produced by Dave Donaldson.  I recommend it highly.
John  Thyhsen  / Philly pops- Peter Nero Conductor...
 
All of us in the Philly pops trumpet section love the shelves/mute holder made by David Donaldson. They are a beautiful product and every trumpet player should own one.
Philly Pops trumpet section....Peter Nero conductor