Flutes need a Clean, Oil, Adjust (COA) at least once every couple of years, more often if they are used in marching band or kept out of their cases. At Hallie's Studio, a COA includes removing the mechanism, knock pins, oiling the mechanism, polishing the head, body, and foot joint tubes, polishing the individual keys and rods, shimming the pads to ensure a correct seal, adjusting, removing most dents, and play testing. A COA does not include replacing any pads, repairing any bent tube or mechanism, replacing head cork, or replacing trill key or Eb key corks. Each additional item cost is $40 each.