ShadowofBaconIt’s a wired unit. However, you could always pick up a Bluetooth receiver separately, and add the feature.
Sennheiser also just released a newer model in the GSP line that will replace the Game and PC series, the GSP 670, which is a Wireless closed-back headphone with built-in surround processing. It costs significantly more, but it interests me due to the hybrid pads, Wireless (they include a USB dongle that emits some wireless signal with better quality than Bluetooth, AND the headset also includes Bluetooth 5), adjustable headband clamp, and Sennheiser’s Binaural Engine to process surround which has been really impressive to me from their GSX 1000 external soundcard.
VeganJoyThey put the same software, and a different (but matched) DAC and amp chip into a wireless headset :D
The surround software only works with PC (and Mac?) though, stereo only for consoles and phones. Still really good, no lag with the USB dongle.