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MARTIN PROTOTYPE SIGMA ELECTRIC GUITAR CIRCA 1979-1980. THIS IS AN EXTREMELY RARE PROTOTYPE MADE - Able Auctions
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1981 Martin Sigma SE-28 Acoustic Flattop w/ Cutaway Natural > Guitars Flattop Electric & Acoustic | Rivington Guitars
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MARTIN PROTOTYPE SIGMA ELECTRIC GUITAR CIRCA 1979-1980. THIS IS AN EXTREMELY RARE PROTOTYPE MADE - Able Auctions
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