K&M Konig & Meyer Black Headphone holder 16080. 

A holder for headphones when not in use. The new headphone holder is simply clamped to the tubes of a music stand or microphone stand, etc. and is generally suitable for a tube diameter max. 30 mm. The soft rubber support can easily take two sets of headphones. In addition, 2 in-ear headphones can also be hung on the slotted front of the holder. The headphones are close to hand and out of harm’s way.