Of course they do, why do you think you take normal damage when hyper hammer (with shield still equiped) is shot in the back?
EDIT: and breaks faster
Ao, you seriously think so?
GN Fields and breakable I-Fields surround the entire mobile suit.
You don't deal extra damage for shootng it in the back; what's the point of having a 360 surround field then?
And lol, Ao. You're comparing a physical shield with an actual field barrier.