Four Slots: Four gauges slot are provided in 1mm,2mm,3mm,4mm. The 1mm slot works for extra narrow frets, likes ukuleles.The 2mm slot works for all standard guitars, bass, mandolin, cigar box guitars. The 3mm, 4mm slot works for jumbo frets. That means it 039;ll work on most stringed instruments.High Effective: One flat file, works on fret edge and fret end round. You will experience the amazing efficiency of diamond.Wooden Handle: The hand shank is made of solid wood, excellent grip and smooth operation.Diamond Abrasive: Diamond abrasive way to coarse for this application, use fret erasers makes the frets as smooth as buttery.Durable: It is made of carbon steel and firmly coated with diamond-like grits. That ensure the long life service of this file.Specification:Material: Carbon steel+diamond grits+wood handleColor: BlackSize(LxWxH): About 227x20x20mm/8.9x0.79x0.79inPackage includes:1pc x Guitar Fret Crowning File2pcs x Neck Protection SheetNote:1. Due to the light and screen difference, the item 039;s color may be slightly different from the pictures.2. Please allow 1-2 cm differences due to manual measurement.