Giannini VSC-4 Professional Handcrafted 10-String Viola with Solid Sitka Spruce Top and Hard Case Giannini VSC-4 Professional Handcrafted 10 String Viola W/ Solid Sitka Spruce Top and Hard Case in Natural finish Solid mahogany back, Solid spruce top, and Ebony fretboard/bridge World famous Giannini quality Steel strings; gauge (mm) - 0.22/0.22. 0.28/0.28. 0.45/0.18. 0.51/0.23. 0.70/0.18