Hi Wonky, i just filled out the online form for my OHME charger and it said that Surge protection was automatically selected. it must be a legal requirement. the only option was if you chose the tethered charger you could pay an oncost for the 8m cable instead of 5m.
Having gone for 5m of cable, I found out the hard way that I should have gone for 8m and have just had to spend money on an extension cable.