Just done the T-COM bluetooth into some JSL Sonis 2 ear defenders (as they had yellow rims to match the car and weren't quite as attenuating as the JSL 'compact' ones), the instuctions on here can be found by using search for 'bluetooth'. They work great, very pleased. The ear defenders I got are rated as 31 SNR and they really do silence the car, quite neat though when you rev hard the mic pics up the noise and sound comes through the in ear speakers but in a subdued way. No wires, easy to manage and connect to your phone / sat nav etc. One observation, I am shorter than Garth and my head matches up to the headrest, the presence of the bluetooth device attached to the ear defender makes for me turning my head left a litle akward as it bumps into the headrest. I have to tilt head forward slightly and then turn head. Garth I think who did the build looks tall in his pictures and his head / ears seem to clear the headrest completely and so I don't think he will have experienced this. Not a big drama for occasional use.