Top-of-the-line, Hand-Tied wigs are the most natural looking, they incorporate this monofilament material which is used all throughout the entire wig cap for a completely natural looking scalp appearance.
There are no "wefts" in these hand-tied caps.
(Wefts are the ribbon-like bands.)
With these types of caps, only a natural scalp appearance will be shown throughout the cap, (i.e), if a brisk wind should blow your wig, and separate the hairs, it would only show a natural scalp appearance underneath vs. showing the wefts.
Source:
http://www.wigsite.com/hand_tied_wigs.html