Tuning fork, 440 Hz, with resonance case

For producing and amplifying the sound of the tuning fork (sound becomes audible), for experiments on resonance and interference of sound waves;
Resonance box made of wood, 4 soft buffers at the bottom, insert at the top to hold the 440 Hz tuning fork.
Tuning fork: approx. 32x11.5x172 mm
Resonance box: 175x97x54 mm
Mass: approx. 403 g