Gear Enhancement requires Gold. Gear Enhancement strengthens Gear Main Attribute.An enhanced gear would have a digital tip with a plus sign attaches to its name, which indicates its enhancement level.
Not all gears have the same maximum enhancement level. The higher level and quality the gear owns, the higher maximum enhancement level will belong to it, of course the higher cost. When the enhancement level is over 15, Gold and Enhancement Stones are also required at the same time.