For the third year in a row, Sammy Hagar and Metallica's James Hetfield will turn out and tune down for a good cause. Their annual Acoustic-4-A-Cure concert, a benefit for the Pediatric Cancer Program at UCSF Benioff Children's Hospital, will be held on Sunday, May 15 at the Fillmore in San Francisco.

Joining the two frontmen will be Joe Satriani and Pat Monahan of Train, both of whom have participated in the previous two installments. In addition, the concert will see performances by Tommy Lee, Melissa Etheridge and, shortly before he joins forces with three former members of the Grateful Dead for a summer tour, John Mayer. In prior years, Hagar and Hetfield have shared the stage with Nancy Wilson of Heart, Jerry Cantrell of Alice In Chains, Chad Smith of the Red Hot Chili Peppers and Billie Joe Armstrong of Green Day.

All proceeds will be donated to the hospital to fund their research into children's brain tumors. UCSF Benioff Children's Hospital admits approximately 5,000 children each year, with 2,000 babies born in the hospital.

Tickets go on sale Friday, April 1 at 10AM Pacific at LiveNation. Tickets are $135 for general admission. There are a handful of VIP packages, which include access to an exclusive area to view the concert, interaction with some of the artists, a gift bag, complimentary food & drinks and more, available for $500. There is a two-ticket limit per customer, and all tickets will be issued at Will Call. For complete information, visit Acoustic-4-A-Cure's website.

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