Koss introduced the KSC35 wireless open earphones. The model is made in the format of overhead headphones with ear rotatable rims. According to a press release, the KSC35 uses Bluetooth version 4.2 with a radius of up to 10m. When playing music continuously, the batteries should last for 6 hours. The cable has a remote control with a built-in microphone.
The manufacturer did not specify the size of the speakers, but noted that the drivers use “oxygen-free copper coils” that “improve signal transmission and conductivity”. The stated frequency range is from 15Hz to 25kHz. Sensitivity-101dB. A protective case is included with the KSC35 headphones.