Green equipment above level 70 can be signed, and those that can be mended can be changed at NPC. Sign craftsman OO HH transforms into a master (not transformed) and a craftsman (transformed) HH, see if you have transformed. You can also change someone else's signature to your own, and you can add your signature if it's weird. All the boxes that have been built and opened are signed, so don't do it again. Six pieces of green signature equipment have bonus UUU 10 pieces of green signature equipment have more bonus. Brother is so tired.