l  Silver dual-membrane chestpiece: the big membrane with a diameter of 45.5mm is sensitive for sound collecting,the small membraneis applicable for child.

l  Zinc alloy chestpiece, excellent sound conduction, little acoustic attenuation.

l  Standard dual PVC tube, well-sealed dual sound conduction channel, good resistance to ambient interference, color is optional.

l  Attached transparent multi-pocket bag included.