The late Mr. Ellsworth, of Puyallup, Wash., operated Boogie Body Guitars from the 1970s until I don't know when. Known as a parts supplier as well as a luthier, he had a hand in the early history of both Warmoth and Carvin guitars, and reportedly built some of the parts used by Eddie Van Halen for his famous red Strat-style instrument with the black and white stripes. Here is what's most likely a one-off Boogie Body 4-string mandolin with Fender 1965 pots and knobs, Schaller tuners, a Robin Guitars bridge, twin-blade humbucker, maple neck and rosewood body cap. It's typical for guitar builders to forget that mandolins should have a 10th-fret marker, not a 9th-fret marker, as Ellsworth did here. Also, with all that room on the lower bout, why are the knobs up there where they could interfere with picking?