Any monk with either of the two Improved Ki Strike-feats can use their Crafting Menu to apply some extra temporary damage to their gloves - at NO cost!
Grasshoppers Brass Knuckles:
Duration: 1 Turn per Monk level.
Requirements: Improved Ki Strike 4, Gloves equipped, Atleast 1 AB on the gloves.
Bonus: 1d6 Positive Damage to the Gloves.
Sensei's Brass Knuckles:
Duration: 1 Turn per Monk level.
Requirements: Improved Ki Strike 5, Gloves equipped, Atleast 1 AB on the gloves.
Bonus: 2d6 Positive Damage to the Gloves.