Kerfing for guitars or ukuleles. You will need x4 pieces for a typical guitar. For ukulele x2 lengths will be enough. Mhogany traditional - 720x18x5/1mm Mhogany rounded - 720x18x4mm Mhogany reverse - 720x17x4mm Basswood traditional - 720x18x5/1mm Basswood rounded - 720x18x4mm​