The gauge includes the 3 most common saddle heights (.016", .018", .020") for electric, acoustic, classical and bass guitars. Plus 3 additional sizes (.012", .014", .022") to meet the desire for a lower string position or a stronger pick attack. Precise, smooth stainless steel without the annoying dirty oil found in conventional feeler gauge sets Laser etched sizes (in & mm) & Instrument Type No wear on the engraving Easy to follow instructions printed directly onto the handle This gauge is part of our KEEP IT SIMPLE, SETUP (KISS) method using our precision measuring devices and tool sets