AIAIAI originally designed their flagship TMA-2 headphones to use a modular feature set that allows you to swap out everything from the ear cups to the headbands and even the speaker units. What's most impressive is that the headphones were actually future-proof from the get go.
If you own already own a pair of TMA-2s and were looking to get a wireless pair of headphones, AIAIAI is now offering a Smart Headband that can be added to your existing pair to enable Bluetooth functionality. Everything you need is integrated into the headband giving you Bluetooth 4.2 connectivity, USB-C charging, and 16 hours of playback time.
From $65, kickstarter.com