These retro styled telephone headsets were everywhere a while back and continue to present itself very desirable. 

My roommate owns one and I have never seen her use it. Functionality wise, the headset doesn’t provide any extra interesting features compared to normal headphones, and are pretty inconvenient in my opinion (since it is advertised as iPhone headsets). However the product nonetheless proves itself to be “cool” and desirable because it modernizes a classical telephone design and brings nostalgia.