The 400F was a flattop variation on the classic Synchromatic 400. It was only offered from about 1945 to 1947 and featured a flat top (with an arched back) and a triangle sound hole along with all of the usual Synchromatic appointments -- a three-piece laminated maple "Miracle Neck", slanted-script Gretsch logo with Synchromatic "Chili Pepper" inlay, slashed humped-block inlays, white and gold sparkle binding, and a stairstep bridge/ Chromatic tailpiece combo.

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