Kala U-Bass Solid Spruce Top, Mahogany Back and Sides, Satin Natural w/ OGBThe Kala U Bass is designed to deliver full sized bass tones into a compact, portable package. This model features a solid spruce top with layered mahogany back and sides, all finished in a satin polyurethane coating. This type of U Bass has polyurethane strings giving it the rich low end and a punchy, smooth tone. This instrument is in very good condition with a couple of dents in the top of the wood.