17Pcs File Tool Set with Carry Case,Premium Grade T12 Drop Forged Alloy Steel…
Premium Forged Alloy Steel: 4 pcs precision large file are made by T12 Drop Forged Alloy Steel, 12 pcs needle files are made by GCR15 bearing steel, high temperature quenching on the surface of the files lead to higher strength and better abrasion resistance.