Steve Vai's "Bo" guitar was stolen outside a benefit concert today (Dec. 12) for Tony MacAlpine. Guitar tech James Shotwell is now offering a reward.

The instrument, a mirror Ibanex JEM with blue LEDs pictured above, vanished from the loading area of the Wiltern Theater in Los Angeles. Vai is appearing there with Zakk Wylde, Billy Sheehan, Derek Sherinian, Mike Portnoy and John 5.

Vai's Facebook page includes detailed information on "Bo," including distinctive wear marks. "This is a one-off, irreplaceable guitar," says Shotwell, who has worked for Dio Disciples' Craig Goldy and the Lucky Strike Live venue in Los Angeles. "Anyone sees this guitar, contact me immediately! This isn't hard to spot and is very unique."

This wouldn't be the first guitar Vai has lost. In fact, his web site lists a number of missing axes that have been "stolen, misplaced or loaned and never returned" – including a guitar used in the "Yankee Rose" video during Vai's tenure in David Lee Roth's band, a black Ibanez loaned to a second studio engineer, and others.

MacAlpine, who is fighting colon cancer, has previously worked in bands with Vai (The Breed) and Sherinian (Planet X) as well as Portnoy and Sheehan (PSMS). Sheehan and John 5 are also Roth band alumni. Tragically, MacAlpine's wife was diagnosed with breast cancer in June.

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