From what I have been able to find, if it is the MAS shaft that came in the 580 driver, the butt diameter was larger at .700″. If it is the MAS shaft in the 510 or 540 Drivers, it was .600. If it is the .700″, you may need to contact Taylor Made to see if they have any grips for it. I am not aware of any after market grips that are still available with a core size that would work. You might try to search online. Sometimes you can find grips like that. We use to sell the old bubble shaft grip that had a core size of .685. We no longer do but I have seen some available from different sources online.