Applying Special Effects to Units

Hello there. I was wondering what the different places special effects can be attached to on units (i.e. the default for the "Special Effect - Create Special Effect On Unit" is overhead.) What would I put there to, say, put a special effect on a footman's sword, for instance?

Thanks in advance.

"weapon" or maybe hand,left or hand,right. note for hand,left and hand,right you must make each string separate and concatonate them