The headphones feature a pretty radical design. The big arch on top is where the signal is fed from the left side of the headphones to the right. They are also a part of an ingenious size adjustment mechanism. In each of the cups there is a massive 53 mm diameter driver. Even though the drivers are huge they are still really sensitivity (98 dB/mW at 1 kHz).
Adjustment mechanism wise the ATH-AD700s is one of the best equipped headphones out there. It easily accommodates any head size in a comfortable manner. Even though the headband pads are relatively small, they never become uncomfortable, which is perhaps due to the fact that the headphones do not weigh more than 280 g. What is really neat about the system is that the "Wings" can alter pitch and angle so that they achieve the right angle of attack at any given position. The only thing you can complain about is the size and looks of the solution, but I would rather look funny than wear a set of uncomfortable headphones.
These small headband pads are covered with some kind of woven fabric which allows you to shed excess heat from your skull through the pads avoiding hot spots. You hairdo will most likely be ruined by use of these headphones, but on the bright side you will never feel uncomfortable. For a size adjustment mechanism the 3D Wing system is definitely one of the most complex I have ever seen. It reminds me a bit of what is featured on AKG K501/601/701 headphones, but without the uncomfortable leather headband.
The back sides of the cups are covered with a hexagonal perforated aluminum cover which looks quite nice and feels durable. They are anodized so they will be hard to scratch, but they will dent easily if you drop them.
The drivers are huge and take up most of the cup real estate.
Like the AKG headphones that I also have, the ATH-AD700s feature a single cable entry in the left ear cup and the have the cables passed through and metal tube (or the metal innards are used as conductor, cannot tell without breaking them apart).