Hi. I'm trying to give my companion a "Pair" of sais. She only uses one at the moment, so I'm trying to use the construction set to make a sai used like a shield. I set it up as armor, using the left hand, and set up as a shield. Now, it works fine for my character. When I equip it, it's being used by my left hand, and it is used like a shield would be. The problem is, when I give it to my companion, her left hand disappears! The sai is there, but the left hand that is holding it is invisible. Why would it work fine for my character but not my companion? I know that it is not the companion, because I tried it with more than one companion. Any ideas?

What does it look like on you, in 3rd person view? A shield should go in the "Wrist" slot.

One reason it works on you might be the fact that there are separate models for the player's hands for third and first person. The shield will take your hand model in 3rd person but not in first person, or so I believe. I'm still learning armor meshes and stuff. If I'm right, your follower's 3rd person hand mesh disappears, and so would yours, but your first person hand mesh is unchanged. Like alphax said, the shield should be placed in the "wrist" slot, but if that makes your wrist disappear, I'm afraid I can't be any help as I have the same problem sometimes and have no idea how to fix it.

First person skeletons (Xbase_anim.1st.nif) has “Shield Bone” as well as “Weapon Bone”. Shields are set to Biped Object “Shield” in the TESCS panel “Armor” (and as Alphax has pointed to body part “Wrist”/Armor in the “Body Part” panel). Therefore no body parts should be replaced/disappear.
Sometimes it is necessary to change the mesh pivot point that it will be reasonably attached by the game engine to the skeleton “Shield” bone. Note that left fingers/hand original animations will be, probably, not correct for the left hand sai. I used shield slot only with custom made animations in order to “convince” NPCs to handle tools (e.g. hammers, axes, shovels for mining slaves).

Thanks for all the advice. With it set to hand, my character holds it in hand and it uses it as a shield. There are no problems in first or third person views; it is just when my companion equips it that her hand disappears. I tried setting the shield sai to the wrist, but it goes through my companions fingers instead of holding it, and a piece of her lower arm is missing. Any other suggestions?