Guitar nut file upper nut groove depth grinding grooving tool,There are four sizes for you to choose from: 024-0.61, 032-0.81, 053-1.35, and 042-1.07. Guitar Nut Files Fret Crowning 1. Ergonomic Design: Featuring a comfortable handle and a long filing, these tools provide ease of use, enabling extended working periods without discomfort or fatigue.
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