I put balenced hilt on my vibrosword and

I wanted what bonuses dose it give to the weapon?

I know it makes the weapon lighter but dose it give the weapon a bonus to damage or dose it just take emcombrince away?

The balanced hilt, by itself, gives the weapon the Accurate (+1) quality. This is described in the Weapon Qualities section of that chapter.

You can also add mods to the balanced hilt, as listed: another Accurate (+1) mod, and a mod that decreases the weapon's encumbrance (these are separate mods).

None of these affect the damage outright, though having two Accurate mods increases your chances of rolling more successes.

Read page 187 to make sure you understand how attachments and mods both work.

Ok thanks I will afb right now