You are a master of magic item creation.
Benefit: You gain a +4 bonus to any skill check made to complete a magic item you are creating (normally this is a Spellcraft check, but sometimes other skills are used). You create magic items in half the normal hours per day (4 hours for one day of work, or two hours for a days work if you increase your completion DC by 5). As long as the total time spent on item creation does not exceed 8 hours per day, you can accomplish multiple days work on an item in a single day.
See Item Creation for more details on item creation and the time required.
Adventurer’s Handbook: Genius Guide Volume 1