The Isaac Foundation's (http://www.theisaacfoundation.com/) mission is to fund innovative research projects that aim to find a cure for MPS, a rare, debilitating, and devastating disease. Double Treble donated a guitar strap to the foundation so they could give John Mayer a small token of appreciation for his involvement with them. Double Treble salutes The Isaac Foundation and Mr. Mayer for their good deeds.
Here are a couple of shots of John with his personalized guitar strap.